mirror of
https://github.com/joncampbell123/dosbox-x.git
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1147 lines
40 KiB
C++
1147 lines
40 KiB
C++
/*
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* Copyright (C) 2002-2021 The DOSBox Team
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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*/
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#ifndef DOSBOX_VGA_H
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#define DOSBOX_VGA_H
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#include "pic.h"
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#include <math.h> /* for fabs */
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#define VGA_LFB_MAPPED
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#define S3_LFB_BASE_DEFAULT 0xE0000000u
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class PageHandler;
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enum VGAModes {
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M_CGA2, // 0
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M_CGA4,
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M_EGA,
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M_VGA,
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M_LIN4,
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M_LIN8, // 5
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M_LIN15,
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M_LIN16,
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M_LIN24,
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M_LIN32,
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M_TEXT, // 10
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M_HERC_GFX,
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M_HERC_TEXT,
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M_CGA16,
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M_TANDY2,
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M_TANDY4, // 15
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M_TANDY16,
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M_TANDY_TEXT,
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M_AMSTRAD,
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M_PC98,
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M_FM_TOWNS, // 20 STUB
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M_PACKED4,
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M_DCGA,
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M_ERROR,
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M_MAX
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};
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extern const char* const mode_texts[M_MAX];
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enum VGA_Vsync {
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VS_Off,
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VS_On,
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VS_Force,
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VS_Host,
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};
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struct vsync_state {
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double period;
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bool manual; // use manual vsync timing
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bool persistent; // use persistent timer (to keep in sync even after internal mode switches)
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bool faithful; // use faithful framerate adjustment
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};
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extern struct vsync_state vsync;
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extern float uservsyncjolt;
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#define CLK_25 25175u
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#define CLK_28 28322u
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#define MIN_VCO 180000u
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#define MAX_VCO 360000u
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#define S3_CLOCK_REF 14318u /* KHz */
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#define S3_CLOCK(_M,_N,_R) ((S3_CLOCK_REF * (((Bitu)_M) + 2ul)) / ((((Bitu)_N) + 2ul) * ((Bitu)1ul << ((Bitu)_R))))
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#define S3_MAX_CLOCK 150000u /* KHz */
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#define S3_XGA_1024 0x00u
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#define S3_XGA_1152 0x01u
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#define S3_XGA_640 0x40u
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#define S3_XGA_800 0x80u
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#define S3_XGA_1280 0xc0u
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#define S3_XGA_1600 0x81u
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#define S3_XGA_WMASK (S3_XGA_640|S3_XGA_800|S3_XGA_1024|S3_XGA_1152|S3_XGA_1280)
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#define S3_XGA_8BPP 0x00u
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#define S3_XGA_16BPP 0x10u
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#define S3_XGA_32BPP 0x30u
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#define S3_XGA_CMASK (S3_XGA_8BPP|S3_XGA_16BPP|S3_XGA_32BPP)
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typedef struct {
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bool attrindex;
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} VGA_Internal;
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typedef struct {
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/* Video drawing */
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Bitu display_start;
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Bitu real_start;
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bool retrace; /* A retrace is active */
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Bitu scan_len;
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Bitu cursor_start;
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/* Some other screen related variables */
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Bitu line_compare;
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bool chained; /* Enable or Disabled Chain 4 Mode */
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bool compatible_chain4;
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/* Pixel Scrolling */
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uint8_t pel_panning; /* Amount of pixels to skip when starting horizontal line */
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uint8_t hlines_skip;
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uint8_t bytes_skip;
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uint8_t addr_shift;
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/* Specific stuff memory write/read handling */
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uint8_t read_mode;
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uint8_t write_mode;
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uint8_t read_map_select;
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uint8_t color_dont_care;
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uint8_t color_compare;
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uint8_t data_rotate;
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uint8_t raster_op;
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uint32_t full_bit_mask;
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uint32_t full_map_mask;
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uint32_t full_not_map_mask;
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uint32_t full_set_reset;
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uint32_t full_not_enable_set_reset;
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uint32_t full_enable_set_reset;
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uint32_t full_enable_and_set_reset;
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} VGA_Config;
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typedef enum {
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DRAWLINE,
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EGALINE
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} Drawmode;
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enum MonochromeColor
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{
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Green,
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Amber,
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Gray,
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White,
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First = Green,
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Last = White
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};
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inline MonochromeColor& operator++(MonochromeColor& color)
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{
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color = static_cast<MonochromeColor>(static_cast<unsigned>(color)+1);
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return color;
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}
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typedef struct {
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bool resizing;
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Bitu width;
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Bitu height;
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Bitu blocks;
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Bitu address;
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Bitu panning;
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Bitu bytes_skip;
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uint8_t *linear_base;
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Bitu linear_mask;
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Bitu planar_mask;
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Bitu address_add;
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Bitu line_length;
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Bitu address_line_total;
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Bitu address_line;
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Bitu lines_total;
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Bitu vblank_skip;
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Bitu lines_done;
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Bitu split_line;
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Bitu byte_panning_shift;
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Bitu render_step,render_max;
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struct {
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double framestart;
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double vrstart, vrend; // V-retrace
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double hrstart, hrend; // H-retrace
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double hblkstart, hblkend; // H-blanking
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double vblkstart, vblkend; // V-Blanking
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double vdend, vtotal;
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double hdend, htotal;
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float singleline_delay;
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} delay;
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double screen_ratio;
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uint8_t font[516*1024]; /* enlarged to 516KB for PC-98 character font data (256*16) + (128*2*128*16) */
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uint8_t * font_tables[2];
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Bitu blinking;
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bool blink;
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bool char9dot;
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struct {
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Bitu address;
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uint8_t sline,eline;
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uint8_t count,delay;
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bool blinkon;
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uint8_t enabled;
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} cursor;
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Drawmode mode;
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bool has_split;
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bool vret_triggered;
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bool vga_override;
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bool doublescan_set;
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bool doublescan_effect;
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bool char9_set;
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Bitu bpp;
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double clock;
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double oscclock;
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uint8_t cga_snow[80]; // one bit per horizontal column where snow should occur
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/*Color and brightness for monochrome display*/
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MonochromeColor monochrome_pal;
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uint8_t monochrome_bright;
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} VGA_Draw;
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/* enable switch for the "alternative video system" */
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extern bool vga_alt_new_mode;
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/* NTS: Usage of this general struct will vary between the various video modes.
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*
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* MDA/Hercules/CGA/PCjr/Tandy: Video hardware is based on the 6845 which
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* counts horizontal AND vertical timing based on character cells. The
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* fact that vertical timing is based on character cells is the reason
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* why changing character cell height requires reprogramming the vertical
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* timings. Most video modes are not entirely a multiple of the character
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* cell height, which is why the 6845 has a "vertical adjust" to add to
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* the total. For example, CGA produces a video signal with NTSC timing
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* by programming enough character cells vertically with a vertical adjust
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* to bring video output to the 262 scanlines required by one field of
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* NTSC video, or 524 scanlines per frame. This isn't quite NTSC since
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* CGA does not emit the half-a-scanline needed for interlaced (to produce
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* 262.5 lines per field or 525 scanlines per frame) but it happens to
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* work with most TV sets (although incompatible with Happauge video
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* capture cards).
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*
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* Note that the CGA is not the only 80s hardware to emit non-interlaced
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* NTSC, most video game consoles of the time period do as well. Your
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* old Nintendo Entertainment System does it too.
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*
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* Because of the character cell-based vertical timing, CGA emulation here
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* will probably not rely so much on vert.total as it will on counting
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* scan lines of the character cell.
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*
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*
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* EGA/VGA/SVGA: Horizontal timing is based on character cells (which
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* varies according to the mode and configuration). Vertical timing is
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* based on scanlines, which is why it is easy to change character cell
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* height without having to reprogram vertical timing.
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*
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* Because of that, VGA emulation will count vertical timing entirely by
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* vert.current and vert.total.
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*
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*
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* MCGA: Not sure. This is weird hardware. Needs more study. It looks a
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* lot like the marriage of CGA with a VGA DAC and a 256-color mode tied
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* to 64KB of memory, and a CRTC that emulates a 6845 but generally ignores
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* some horizontal and vertical values and hacks others and possibly
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* carries video line doubling circuitry in order to produce 400-line video
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* from 200-line video timings (except the 640x480 2-color mode).
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*
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*
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* NEC PC-98: Two instances of this C++ class will be used in parallel,
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* with the same dot clock, to emulate the text and graphics "layers" of
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* PC-98 video. Both instances will generally have the same horizontal
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* and vertical timing but they don't have to, in which case the VGA
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* render code will generate the gibberish that would occur on real
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* hardware when the two are not synchronized.
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*/
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typedef struct VGA_Experimental_Model_1_t {
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template <typename T> struct pix_char_t {
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T pixels;
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T chars;
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pix_char_t() { }
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pix_char_t(const T val) : pixels(val), chars(val) { }
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};
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template <typename T> struct start_end_t {
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T start;
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T end;
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start_end_t() { }
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start_end_t(const T val) : start(val), end(val) { }
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start_end_t(const unsigned int val) : start(val), end(val) { }
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};
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/* pixel 0 is start of display area.
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* next scanline starts when current == total before drawing next pixel.
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*/
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struct general_dim {
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// CRTC counter address (H) / CRTC counter address at start of line (V)
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unsigned int crtc_addr = 0;
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// CRTC counter address to add per character clock (H) / per scan line (V)
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unsigned int crtc_addr_add = 0;
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// current position in pixels within scan line (H) / number of scan line (V)
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pix_char_t<unsigned int> current = 0;
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// total pixels in scan line (H) / total scan lines (V)
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pix_char_t<unsigned int> total = 0;
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// first pixel (H) / scan line (V) that active display STARTs, ENDs (start == 0 usually)
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start_end_t< pix_char_t<unsigned int> > active = 0;
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// first pixel (H) / scan line (V) that blanking BEGINs, ENDs
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start_end_t< pix_char_t<unsigned int> > blank = 0;
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// first pixel (H) / scan line (V) that retrace BEGINs, ENDs
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start_end_t< pix_char_t<unsigned int> > retrace = 0;
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// largest horizontal active.end value during the entire frame (H) for demos like DoWhackaDo.
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// largest vertical active.end value during the entire frame (V).
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// reset to active.end at start of active display. (H/V)
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pix_char_t<unsigned int> active_max = 0;
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// start of scan line (H) / frame (V) PIC full index time
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pic_tickindex_t time_begin = 0;
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// length of scan line (H) / length of frame (V)
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pic_tickindex_t time_duration = 0;
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// current pixel position (H) / scan line (V) within character cell
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unsigned char current_char_pixel = 0;
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// width (H) / scan lines (V) of a character cell
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unsigned char char_pixels = 0;
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// bit mask for character row compare
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unsigned char char_pixel_mask = 0;
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bool blank_enable = false; // blank enable
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bool display_enable = false; // display enable (active area)
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bool retrace_enable = false; // retrace enable
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};
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// NTS: If start < end, cell starts with enable = false. at start of line,
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// toggle enable (true) when line == start, then toggle enable (false) when
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// line == end, then draw.
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//
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// If start >= end, cell starts with enable = true, at start of line,
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// toggle enable (false) when line == start, then toggle enable (true) when
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// line == end, then draw.
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bool cursor_enable = false; // if set, show cursor
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unsigned char cursor_start = 0; // cursor starts on this line (toggle cursor enable)
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unsigned char cursor_end = 0; // cursor stops on this line (first line to toggle again to disable)
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unsigned int crtc_cursor_addr = 0; // crtc address to display cursor at
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unsigned int crtc_mask = 0; // draw from memory ((addr & mask) + add)
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unsigned int crtc_add = 0; // NTS: For best results crtc_add should only change bits that are masked off
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inline unsigned int crtc_addr_fetch(void) const {
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return (horz.crtc_addr & crtc_mask) + crtc_add;
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}
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inline unsigned int crtc_addr_fetch_and_advance(void) {
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const unsigned int ret = crtc_addr_fetch();
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horz.crtc_addr += horz.crtc_addr_add;
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return ret;
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}
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unsigned int raster_scanline = 0; // actual scan line out to display
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unsigned char doublescan_count = 0; // VGA doublescan counter
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unsigned char doublescan_max = 0; // Advance scanline at this count
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// NTS: horz.char_pixels == 8 for CGA/MDA/etc and EGA/VGA text, but EGA/VGA can select 9 pixels/char.
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// VGA 320x200x256-color mode will have 4 pixels/char. A hacked version of 320x200x256-color mode
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// in which the 8BIT bit is cleared (which makes it a sort of 640x200x256-color-ish mode that
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// reveals the intermediate register states normally hidden) will have 8 pixels/char.
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//
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// MCGA 320x200x256-color will have horz.char_pixels == 8. A register dump from real hardware shows
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// that Mode 13 has the same horizontal timings as every other mode (as if 320x200 CGA graphics!).
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// This is very different from VGA where 320x200x256 is programmed as if a 640x200 graphics mode.
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//
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// PC-98 will render as if horz.char_pixels == 8 on the text layer. It may set horz.char_pixels == 16
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// on some text cells if the hardware is to render a double-wide character. The graphics layer is
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// generally programmed into WORDs mode which means horz.char_pixels == 16 at all times. If it is
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// ever programmed into byte mode then it will set horz.char_pixels == 8.
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struct dotclock_t {
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double rate_invmult = 0;
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double rate_mult = 0;
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double rate = 0;
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pic_tickindex_t base = 0;
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signed long long ticks = 0;
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signed long long ticks_prev = 0;
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void reset(const pic_tickindex_t now) {
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ticks = ticks_prev = 0;
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base = now;
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}
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// do not call unless all ticks processed
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void set_rate(const double new_rate,const pic_tickindex_t now) {
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if (rate != new_rate) {
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update(now);
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rebase();
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if ((rate <= 0) || (fabs(now - base) > (0.5 * rate_invmult)))
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base = now;
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if (new_rate > 0) {
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rate_invmult = 1000 / new_rate; /* Hz -> ms */
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rate_mult = new_rate / 1000; /* ms -> Hz */
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rate = new_rate;
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}
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else {
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rate_invmult = 0;
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rate_mult = 0;
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rate = 0;
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}
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update(now);
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ticks_prev = ticks;
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}
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}
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inline pic_tickindex_t ticks2pic_relative(const signed long long t,const pic_tickindex_t now) const {
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return (t * rate_invmult) + (base - now);/* group float operations to maintain precision */
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}
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inline pic_tickindex_t ticks2pic(const signed long long t) const {
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return (t * rate_invmult) + base;
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}
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inline signed long long pic2ticks(const pic_tickindex_t now) const {
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/* typecasting rounds down to 0 apparently. floor() is slower. */
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return (signed long long)((now - base) * rate_mult);
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}
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// inline and minimal for performance!
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inline void update(const pic_tickindex_t now) {
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/* NTS: now = PIC_FullIndex() which is time in ms (1/1000 of a sec) */
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ticks = pic2ticks(now);
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}
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// retrival of tick count and reset of counter
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inline signed long long delta_peek(void) const {
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return ticks - ticks_prev;
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}
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inline signed long long delta_get(void) {
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signed long long ret = delta_peek();
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ticks_prev = ticks;
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return ret;
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}
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// rebase of the counter.
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// call this every so often (but not too often) in order to prevent floating point
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// precision loss over time as the numbers get larger and larger.
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void rebase(void) {
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if (rate_mult > 0) {
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base += ticks * rate_invmult;
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ticks = ticks_prev = 0;
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}
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}
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};
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/* integer fraction.
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* If you need more precision (4.1:3 instead of 4:3) just scale up the values (4.1:3 -> 41:30) */
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struct int_fraction_t {
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unsigned int numerator = 0;
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unsigned int denominator = 0;
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int_fraction_t() { }
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int_fraction_t(const unsigned int n,const unsigned int d) : numerator(n), denominator(d) { }
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};
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/* 2D display dimensions */
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struct dimensions_t {
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unsigned int width = 0;
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unsigned int height = 0;
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dimensions_t() { }
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dimensions_t(const unsigned int w,const unsigned int h) : width(w), height(h) { }
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};
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/* 2D coordinate */
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struct int_point2d_t {
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int x = 0;
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int y = 0;
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|
|
|
int_point2d_t() { }
|
|
int_point2d_t(const int nx,const int ny) : x(nx), y(ny) { }
|
|
};
|
|
|
|
// use the dot clock to map advancement of emulator time to dot clock ticks.
|
|
// apply the dot clock ticks against the horizontal and vertical current position
|
|
// to emulate the raster of the video output over time.
|
|
//
|
|
// if anything changes dot clock rate, process all ticks and advance hardware
|
|
// state, then set the rate and process all dot clock ticks after that point
|
|
// at the new rate.
|
|
|
|
dotclock_t dotclock;
|
|
general_dim horz,vert;
|
|
|
|
// monitor emulation
|
|
dimensions_t monitor_display; // image sent to GFX (may include overscan, blanking, etc)
|
|
int_point2d_t monitor_start_point; // pixel(x)/scanline(y) counter of the CRTC that is start of line(x)/frame(y)
|
|
int_fraction_t monitor_aspect_ratio = {4,3}; // display aspect ratio of the video frame
|
|
|
|
// The GFX/scaler system will be sent a frame of dimensions monitor_display.
|
|
// The start of the frame will happen when the CRTC pixel count matches the monitor_start_point.
|
|
// monitor_start_point will be set to 0,0 if DOSBox-X is set only to show active area.
|
|
// it will be set to match on the first clock/scanline of the non-blanking area (overscan), upper left corner if set to do so.
|
|
// it will be set to some point of the blanking area if asked to do so to approximate how a VGA monitor centers the image.
|
|
// finally, a debug mode will be offered to show the ENTIRE frame (htotal/vtotal) with markings for retrace if wanted by the user.
|
|
|
|
// Pointers to draw from. This represents CRTC character clock 0.
|
|
uint8_t* draw_base = NULL;
|
|
|
|
template <typename T> inline const T* drawptr(const size_t offset) const {
|
|
return (const T*)draw_base + offset; /* equiv T* ptr = (T*)draw_base; return &ptr[offset]; */
|
|
}
|
|
|
|
template <typename T> inline T* drawptr_rw(const size_t offset) const {
|
|
return (T*)draw_base + offset; /* equiv T* ptr = (T*)draw_base; return &ptr[offset]; */
|
|
}
|
|
} VGA_Draw_2;
|
|
|
|
typedef struct {
|
|
uint8_t curmode;
|
|
uint16_t originx, originy;
|
|
uint8_t fstackpos, bstackpos;
|
|
uint8_t forestack[4];
|
|
uint8_t backstack[4];
|
|
uint16_t startaddr;
|
|
uint8_t posx, posy;
|
|
uint8_t mc[64][64];
|
|
} VGA_HWCURSOR;
|
|
|
|
typedef struct {
|
|
uint8_t reg_lock1;
|
|
uint8_t reg_lock2;
|
|
uint8_t reg_31;
|
|
uint8_t reg_35;
|
|
uint8_t reg_36; // RAM size
|
|
uint8_t reg_3a; // 4/8/doublepixel bit in there
|
|
uint8_t reg_40; // 8415/A functionality register
|
|
uint8_t reg_41; // BIOS flags
|
|
uint8_t reg_42; // CR42 Mode Control
|
|
uint8_t reg_43;
|
|
uint8_t reg_45; // Hardware graphics cursor
|
|
uint8_t reg_50;
|
|
uint8_t reg_51;
|
|
uint8_t reg_52;
|
|
uint8_t reg_55;
|
|
uint8_t reg_58;
|
|
uint8_t reg_63; // Extended control register
|
|
uint8_t reg_6b; // LFB BIOS scratchpad
|
|
uint8_t ex_hor_overflow;
|
|
uint8_t ex_ver_overflow;
|
|
uint16_t la_window;
|
|
uint8_t misc_control_2;
|
|
uint8_t ext_mem_ctrl;
|
|
Bitu xga_screen_width;
|
|
VGAModes xga_color_mode;
|
|
struct {
|
|
uint8_t r;
|
|
uint8_t n;
|
|
uint8_t m;
|
|
} clk[4],mclk;
|
|
struct {
|
|
uint8_t lock;
|
|
uint8_t cmd;
|
|
} pll;
|
|
VGA_HWCURSOR hgc;
|
|
struct {
|
|
// (MM8180 Primary Stream Control)
|
|
uint8_t psctl_psfc; // [30:28] PSFC Primary Stream Filter Characteristics
|
|
// 0=RGB-8 CLUT or XRGB-32 (X.8.8.8) 3=KRGB-16 (1.5.5.5) 5=RGB-16 (5.6.5)
|
|
uint8_t psctl_psidf; // [26:24] PSIDF Primary Stream Input Data Format
|
|
// 0=Primary Stream 1=..for 2X stretch (replication) 2=..bilinear for 2X stretch (interpolation)
|
|
// (MM8184 Color/Chroma Key Control)
|
|
uint8_t ckctl_b_lb; // [ 7: 0] B/V/Cr KEY (LOW)
|
|
uint8_t ckctl_g_lb; // [15: 8] G/U/Cb KEY (LOW)
|
|
uint8_t ckctl_r_lb; // [23:16] R/Y KEY (LOW)
|
|
uint8_t ckctl_rgb_cc; // [26:24] RGB CC - RGB Color Comparison Precision
|
|
// 0=Compare bit 7 of RGB
|
|
// 1=Compare bits 7-6 of RGB
|
|
// 2=Compare bits 7-5 of RGB
|
|
// 3=Compare bits 7-4 of RGB
|
|
// 4=Compare bits 7-3 of RGB
|
|
// 5=Compare bits 7-2 of RGB
|
|
// 6=Compare bits 7-1 of RGB
|
|
// 7=Compare bits 7-0 of RGB
|
|
uint8_t ckctl_kc; // [28:28] Key Control
|
|
// 0=Use K bit for keying in KRGB-16 (1.5.5.5) mode
|
|
// 1=Enable color or chroma keying for all modes other than KRGB-16
|
|
|
|
// (MM8190 Secondary Stream Control)
|
|
int16_t ssctl_dda_haccum; // [11: 0] DDA Horizontal Accumulator (signed 2's complement)
|
|
// Set to: 2*(W0-1) - (W1-1) [FIXME: Am I reading that right? Datasheet says 2 (W0-1) - (W1-1)
|
|
// Windows 3.1 DCI seems to compute instead: ((2*(W0-1) - (W1-1)) / 2)
|
|
// W0 = line length in pixels before scaling
|
|
// W1 = line length in pixels after scaling
|
|
uint8_t ssctl_sdif; // [26:24] SDIF Secondary Stream Input Data Format
|
|
// 1=YCbCr-16 (4.2.2), 16-240 input range (NTS: known as 'YUY2', 8-bit YUYV, for MPEG playback)
|
|
// 2=YUV-16 (4.2.2), 0-255 input range (NTS: 8-bit YUYV but full range, perhaps appropriate for JPEG)
|
|
// 3=KRGB-16 (1.5.5.5)
|
|
// 4=YUV (2.1.1) (NTS: I think this means planar YUV, U and V are one quarter resolution. Also known in the industry as 4:2:0)
|
|
// 5=RGB-16 (5.6.5)
|
|
// 7=XRGB-32 (X.8.8.8)
|
|
uint8_t ssctl_sfc; // [30:28] SFC - Secondary Stream Filter Characteristics
|
|
// 0=Secondary Stream 1=..linear 0-2-4-2-0, for X stretch 2=..bilinear for 2X to 4X stretch
|
|
// 3=..linear 1-2-2-2-1, for 4X stretch
|
|
|
|
// (MM8194 Chroma Key Upper Bound)
|
|
uint8_t ckctl_b_ub; // [ 7: 0] B/V/Cr KEY (UPPER)
|
|
uint8_t ckctl_g_ub; // [15: 8] G/U/Cb KEY (UPPER)
|
|
uint8_t ckctl_r_ub; // [23:16] R/Y KEY (UPPER)
|
|
|
|
// (MM8198 Secondary Stream Stretch/Filter Constants)
|
|
uint16_t ssctl_k1_hscale; // [10: 0] K1 horizontal scale factor
|
|
// Set to: W0-1, where W0 is width of pixels of the initial output window before scaling
|
|
int16_t ssctl_k2_hscale; // [26:16] K2 horizontal scale factor
|
|
// Set to: W0-W1, where W1 is the width of pixels of the final scaled output window.
|
|
// "This value is signed and will always be negative" (FIXME: Does that imply the card cannot *downscale* YUV overlays?)
|
|
|
|
// (MM81A0 Blend Control)
|
|
uint8_t blendctl_ks; // [ 4: 2] secondary stream blend coefficient
|
|
uint8_t blendctl_kp; // [12:10] primary stream blend coefficient
|
|
uint8_t blendctl_composemode;//[26:24] compose mode
|
|
// 0=secondary stream opaque overlay on primary stream
|
|
// 1=primary stream opaque overlay on secondary stream
|
|
// 2=dissolve, [Pp x Kp + Ps x (8 - Kp)]/8, ignore Ks
|
|
// 3=Fade, [Pp x Kp + Ps x Ks]/8, where Kp + Ks must be <= 8
|
|
// 5=Color key on primary stream (secondary stream overlay on primary stream)
|
|
// 6=Color or chroma key on secondary stream (primary stream overlay on secondary stream)
|
|
|
|
// (MM81C0 Primary Stream Frame Buffer Address 0)
|
|
// (MM81C4 Primary Stream Frame Buffer Address 1)
|
|
uint32_t ps_fba[2]; // [21: 0] Primary Buffer Address
|
|
|
|
// (MM81C8 Primary Stream Stride)
|
|
uint32_t ps_stride; // [11: 0] Primary Stream Stride
|
|
|
|
// (MM81CC Double Buffer/LPB Support)
|
|
uint8_t ps_bufsel; // [ 0: 0] Primary Stream Buffer Select (0=address 0 1=address 1)
|
|
uint8_t ss_bufsel; // [ 2: 1] Secondary Stream Buffer Select
|
|
// 0=address 0
|
|
// 1=address 1
|
|
// 2=address (LPB input buffer select ^ 0) and opposite is for LPB
|
|
// 3=address (LPB input buffer select ^ 1) and opposite is for LPB
|
|
uint8_t lpb_in_bufsel; // [ 4: 4] LIS LPB Input Buffer Select
|
|
uint8_t lpb_in_bufselloading;//[ 5: 5] LSL LPB Input Buffer Select Loading
|
|
uint8_t lpb_in_bufseltoggle;// [ 6: 6] LST LPB Input Buffer Select Toggle
|
|
|
|
// (MM81D0 Secondary Stream Frame Buffer Address 0)
|
|
// (MM81D4 Secondary Stream Frame Buffer Address 1)
|
|
uint32_t ss_fba[2]; // [21: 0] Secondary Buffer Address
|
|
|
|
// (MM81D8 Secondary Stream Stride)
|
|
uint32_t ss_stride; // [11: 0] Secondary Stream Stride
|
|
|
|
// (MM81DC Opaque Overlay Control)
|
|
uint16_t ooc_pixfetch_stop; // [12: 3] Pixel stop fetch
|
|
uint16_t ooc_pixfetch_resume;// [28:19] Pixel resume fetch
|
|
uint8_t ooc_tss; // [30:30] Top Stream Select 0=Secondary on top 1=Primary on top
|
|
uint8_t ooc_ooc_enable; // [31:31] Opaque Overlay Control Enable 0=disabled 1=enabled
|
|
|
|
// (MM81E0 K1 Vertical Scale Factor)
|
|
uint16_t k1_vscale_factor; // [10: 0] K1 Vertical Scale Factor
|
|
// Set to: [height in lines of initial output window before scaling] - 1
|
|
|
|
// (MM81E4 K2 Vertical Scale Factor)
|
|
int16_t k2_vscale_factor; // [10: 0] K2 Vertical Scale Factor
|
|
// Set to: (height in lines before scale) - (height in lines of final window after scaling)
|
|
|
|
// (MM81E8 DDA Vertical Accumulator Initial Value)
|
|
int16_t dda_vaccum_iv; // [11: 0] DDA Vertical Accumulator
|
|
// Set to: -((height in lines after scaling) - 1)
|
|
uint8_t evf; // [15:15] EVF Enable Vertical Filtering
|
|
|
|
// (MM81EC Stream FIFO and RAS Controls)
|
|
uint8_t fifo_alloc_ps; // Interpretation of [4:0], where 5 bits are number of slots alloted to secondary stream.
|
|
// N = secondary stream slots This value is set to 24 - N
|
|
uint8_t fifo_alloc_ss; // Interpretation of [4:0], set to N (up to 24)
|
|
uint8_t fifo_ss_threshhold; // Threshhold at which FIFO refill of secondary stream is triggered (low water point). Must be <= alloc_ss
|
|
uint8_t fifo_ps_threshhold; // Threshhold at which FIFO refill of primary stream is triggered (low water point). Must be <= alloc_ps
|
|
uint8_t ras_rl; // [15:15] RL RAS Low Time Control
|
|
uint8_t ras_rp; // [16:16] RP RAS Pre-Charge Control
|
|
uint8_t edo_wsctl; // [18:18] EDO Memory Wait State Control
|
|
|
|
// (MM81F0 Primary Stream Window Start Coordinates)
|
|
uint16_t pswnd_start_y; // [10: 0] Primary Stream Y start
|
|
// Set to: Screen line number + 1
|
|
uint16_t pswnd_start_x; // [26:16] Primary Stream X start
|
|
// Set to: Screen pixel number + 1
|
|
|
|
// (MM81F4 Primary Stream Window Size)
|
|
uint16_t pswnd_height; // [10: 0] Primary Stream Height
|
|
// Set to: number of lines
|
|
uint16_t pswnd_width; // [26:16] Primary Stream Width
|
|
// Set to: number of pixels - 1
|
|
|
|
// (MM81F8 Secondary Stream Window Start Coordinates)
|
|
uint16_t sswnd_start_y; // [10: 0] Secondary Stream Y start
|
|
// Set to: Screen line number + 1
|
|
uint16_t sswnd_start_x; // [26:16] Secondary Stream X start
|
|
// Set to: Screen pixel number + 1
|
|
|
|
// (MM81FC Secondary Stream Window Size)
|
|
uint16_t sswnd_height; // [10: 0] Secondary Stream Height
|
|
// Set to: number of lines
|
|
uint16_t sswnd_width; // [26:16] Secondary Stream Width
|
|
// Set to: number of pixels - 1
|
|
} streams; // hardware YUV/RGB overlay i.e. for MPEG playback
|
|
} VGA_S3;
|
|
|
|
typedef struct {
|
|
uint8_t mode_control;
|
|
uint8_t enable_bits;
|
|
bool blend;
|
|
} VGA_HERC;
|
|
|
|
typedef struct {
|
|
uint32_t mask_plane;
|
|
uint8_t write_plane;
|
|
uint8_t read_plane;
|
|
uint8_t border_color;
|
|
} VGA_AMSTRAD;
|
|
|
|
typedef struct {
|
|
uint8_t index;
|
|
uint8_t htotal;
|
|
uint8_t hdend;
|
|
uint8_t hsyncp;
|
|
uint8_t hsyncw;
|
|
uint8_t vtotal;
|
|
uint8_t vdend;
|
|
uint8_t vadjust;
|
|
uint8_t vsyncp;
|
|
uint8_t vsyncw;
|
|
uint8_t max_scanline;
|
|
uint16_t lightpen;
|
|
bool lightpen_triggered;
|
|
uint8_t cursor_start;
|
|
uint8_t cursor_end;
|
|
uint8_t mcga_mode_control;
|
|
} VGA_OTHER;
|
|
|
|
typedef struct {
|
|
uint8_t pcjr_flipflop;
|
|
uint8_t mode_control;
|
|
uint8_t color_select;
|
|
uint8_t disp_bank;
|
|
uint8_t reg_index;
|
|
uint8_t gfx_control;
|
|
uint8_t palette_mask;
|
|
uint8_t extended_ram;
|
|
uint8_t border_color;
|
|
uint8_t line_mask, line_shift;
|
|
uint8_t draw_bank, mem_bank;
|
|
uint8_t *draw_base, *mem_base;
|
|
Bitu addr_mask;
|
|
} VGA_TANDY;
|
|
|
|
typedef struct {
|
|
uint8_t index;
|
|
uint8_t reset;
|
|
uint8_t clocking_mode;
|
|
uint8_t map_mask;
|
|
uint8_t character_map_select;
|
|
uint8_t memory_mode;
|
|
} VGA_Seq;
|
|
|
|
typedef struct {
|
|
uint8_t palette[16];
|
|
uint8_t mode_control;
|
|
uint8_t horizontal_pel_panning;
|
|
uint8_t overscan_color;
|
|
uint8_t color_plane_enable;
|
|
uint8_t color_select;
|
|
uint8_t index;
|
|
uint8_t disabled; // Used for disabling the screen.
|
|
// Bit0: screen disabled by attribute controller index
|
|
// Bit1: screen disabled by sequencer index 1 bit 5
|
|
// These are put together in one variable for performance reasons:
|
|
// the line drawing function is called maybe 60*480=28800 times/s,
|
|
// and we only need to check one variable for zero this way.
|
|
} VGA_Attr;
|
|
|
|
typedef struct {
|
|
uint8_t horizontal_total;
|
|
uint8_t horizontal_display_end;
|
|
uint8_t start_horizontal_blanking;
|
|
uint8_t end_horizontal_blanking;
|
|
uint8_t start_horizontal_retrace;
|
|
uint8_t end_horizontal_retrace;
|
|
uint8_t vertical_total;
|
|
uint8_t overflow;
|
|
uint8_t preset_row_scan;
|
|
uint8_t maximum_scan_line;
|
|
uint8_t cursor_start;
|
|
uint8_t cursor_end;
|
|
uint8_t start_address_high;
|
|
uint8_t start_address_low;
|
|
uint8_t cursor_location_high;
|
|
uint8_t cursor_location_low;
|
|
uint8_t vertical_retrace_start;
|
|
uint8_t vertical_retrace_end;
|
|
uint8_t vertical_display_end;
|
|
uint8_t offset;
|
|
uint8_t underline_location;
|
|
uint8_t start_vertical_blanking;
|
|
uint8_t end_vertical_blanking;
|
|
uint8_t mode_control;
|
|
uint8_t line_compare;
|
|
|
|
uint8_t index;
|
|
bool read_only;
|
|
} VGA_Crtc;
|
|
|
|
typedef struct {
|
|
uint8_t index;
|
|
uint8_t set_reset;
|
|
uint8_t enable_set_reset;
|
|
uint8_t color_compare;
|
|
uint8_t data_rotate;
|
|
uint8_t read_map_select;
|
|
uint8_t mode;
|
|
uint8_t miscellaneous;
|
|
uint8_t color_dont_care;
|
|
uint8_t bit_mask;
|
|
} VGA_Gfx;
|
|
|
|
typedef struct {
|
|
uint8_t red;
|
|
uint8_t green;
|
|
uint8_t blue;
|
|
} RGBEntry;
|
|
|
|
typedef struct {
|
|
uint8_t bits; /* DAC bits, usually 6 or 8 */
|
|
uint8_t pel_mask;
|
|
uint8_t pel_index;
|
|
uint8_t state;
|
|
uint8_t write_index;
|
|
uint8_t read_index;
|
|
Bitu first_changed;
|
|
uint8_t combine[16];
|
|
RGBEntry rgb[0x100];
|
|
uint16_t xlat16[256];
|
|
uint32_t xlat32[256];
|
|
uint8_t hidac_counter;
|
|
uint8_t reg02;
|
|
} VGA_Dac;
|
|
|
|
typedef struct {
|
|
Bitu readStart, writeStart;
|
|
Bitu bankMask;
|
|
Bitu bank_read_full;
|
|
Bitu bank_write_full;
|
|
uint8_t bank_read;
|
|
uint8_t bank_write;
|
|
Bitu bank_size;
|
|
} VGA_SVGA;
|
|
|
|
typedef union CGA_Latch {
|
|
uint16_t d;
|
|
uint8_t b[2] = {};
|
|
|
|
CGA_Latch() { }
|
|
CGA_Latch(const uint16_t raw) : d(raw) { }
|
|
} CGA_Latch;
|
|
|
|
typedef union VGA_Latch {
|
|
uint32_t d;
|
|
uint8_t b[4] = {};
|
|
|
|
VGA_Latch() { }
|
|
VGA_Latch(const uint32_t raw) : d(raw) { }
|
|
} VGA_Latch;
|
|
|
|
typedef struct VGA_Memory_t {
|
|
uint8_t* linear = NULL;
|
|
uint8_t* linear_orgptr = NULL;
|
|
|
|
uint32_t memsize = 0;
|
|
uint32_t memmask = 0;
|
|
uint32_t memmask_crtc = 0; // in CRTC-visible units (depends on byte/word/dword mode)
|
|
} VGA_Memory;
|
|
|
|
typedef struct {
|
|
uint32_t page;
|
|
uint32_t addr;
|
|
uint32_t mask;
|
|
PageHandler *handler;
|
|
} VGA_LFB;
|
|
|
|
static const size_t VGA_Draw_2_elem = 2;
|
|
|
|
typedef struct VGA_Type_t {
|
|
VGAModes mode = {}; /* The mode the vga system is in */
|
|
VGAModes lastmode = {};
|
|
uint8_t misc_output = 0;
|
|
VGA_Draw_2 draw_2[VGA_Draw_2_elem]; /* new parallel video emulation. PC-98 mode will use both, all others only the first. */
|
|
VGA_Draw draw = {};
|
|
VGA_Config config = {};
|
|
VGA_Internal internal = {};
|
|
/* Internal module groups */
|
|
VGA_Seq seq = {};
|
|
VGA_Attr attr = {};
|
|
VGA_Crtc crtc = {};
|
|
VGA_Gfx gfx = {};
|
|
VGA_Dac dac = {};
|
|
VGA_Latch latch;
|
|
VGA_S3 s3 = {};
|
|
VGA_SVGA svga = {};
|
|
VGA_HERC herc = {};
|
|
VGA_TANDY tandy = {};
|
|
VGA_AMSTRAD amstrad = {};
|
|
VGA_OTHER other = {};
|
|
VGA_Memory mem;
|
|
VGA_LFB lfb = {};
|
|
} VGA_Type;
|
|
|
|
|
|
/* Hercules Palette function */
|
|
void Herc_Palette(void);
|
|
|
|
/* CGA Mono Palette function */
|
|
void Mono_CGA_Palette(void);
|
|
|
|
/* Functions for different resolutions */
|
|
void VGA_SetMode(VGAModes mode);
|
|
void VGA_DetermineMode(void);
|
|
void VGA_SetupHandlers(void);
|
|
void VGA_StartResize(Bitu delay=50);
|
|
void VGA_SetupDrawing(Bitu val);
|
|
void VGA_CheckScanLength(void);
|
|
void VGA_ChangedBank(void);
|
|
|
|
/* Some DAC/Attribute functions */
|
|
void VGA_DAC_CombineColor(uint8_t attr,uint8_t pal);
|
|
void VGA_DAC_SetEntry(Bitu entry,uint8_t red,uint8_t green,uint8_t blue);
|
|
void VGA_ATTR_SetPalette(uint8_t index,uint8_t val);
|
|
|
|
typedef enum {CGA, EGA, MONO} EGAMonitorMode;
|
|
|
|
typedef enum {AC_4x4, AC_low4/*4low*/} ACPalRemapMode;
|
|
|
|
extern unsigned char VGA_AC_remap;
|
|
|
|
void VGA_ATTR_SetEGAMonitorPalette(EGAMonitorMode m);
|
|
|
|
/* The VGA Subfunction startups */
|
|
void VGA_SetupAttr(void);
|
|
void VGA_SetupMemory(void);
|
|
void VGA_SetupDAC(void);
|
|
void VGA_SetupMisc(void);
|
|
void VGA_SetupGFX(void);
|
|
void VGA_SetupSEQ(void);
|
|
void VGA_SetupOther(void);
|
|
void VGA_SetupXGA(void);
|
|
|
|
/* Some Support Functions */
|
|
void VGA_SetClock(Bitu which,Bitu target);
|
|
void VGA_StartUpdateLFB(void);
|
|
void VGA_SetBlinking(Bitu enabled);
|
|
void VGA_SetCGA2Table(uint8_t val0,uint8_t val1);
|
|
void VGA_SetCGA4Table(uint8_t val0,uint8_t val1,uint8_t val2,uint8_t val3);
|
|
void VGA_ActivateHardwareCursor(void);
|
|
void VGA_KillDrawing(void);
|
|
|
|
void VGA_SetOverride(bool vga_override);
|
|
|
|
extern VGA_Type vga;
|
|
|
|
/* Support for modular SVGA implementation */
|
|
/* Video mode extra data to be passed to FinishSetMode_SVGA().
|
|
This structure will be in flux until all drivers (including S3)
|
|
are properly separated. Right now it contains only three overflow
|
|
fields in S3 format and relies on drivers re-interpreting those.
|
|
For reference:
|
|
ver_overflow:X|line_comp10|X|vretrace10|X|vbstart10|vdispend10|vtotal10
|
|
hor_overflow:X|X|X|hretrace8|X|hblank8|hdispend8|htotal8
|
|
offset is not currently used by drivers (useful only for S3 itself)
|
|
It also contains basic int10 mode data - number, vtotal, htotal
|
|
*/
|
|
typedef struct {
|
|
uint8_t ver_overflow;
|
|
uint8_t hor_overflow;
|
|
Bitu offset;
|
|
Bitu modeNo;
|
|
Bitu htotal;
|
|
Bitu vtotal;
|
|
} VGA_ModeExtraData;
|
|
|
|
// Vector function prototypes
|
|
typedef void (*tWritePort)(Bitu reg,Bitu val,Bitu iolen);
|
|
typedef Bitu (*tReadPort)(Bitu reg,Bitu iolen);
|
|
typedef void (*tFinishSetMode)(Bitu crtc_base, VGA_ModeExtraData* modeData);
|
|
typedef void (*tDetermineMode)();
|
|
typedef void (*tSetClock)(Bitu which,Bitu target);
|
|
typedef Bitu (*tGetClock)();
|
|
typedef bool (*tHWCursorActive)();
|
|
typedef bool (*tAcceptsMode)(Bitu modeNo);
|
|
typedef void (*tSetupDAC)();
|
|
typedef void (*tINT10Extensions)();
|
|
|
|
struct SVGA_Driver {
|
|
tWritePort write_p3d5;
|
|
tReadPort read_p3d5;
|
|
tWritePort write_p3c5;
|
|
tReadPort read_p3c5;
|
|
tWritePort write_p3c0;
|
|
tReadPort read_p3c1;
|
|
tWritePort write_p3cf;
|
|
tReadPort read_p3cf;
|
|
|
|
tFinishSetMode set_video_mode;
|
|
tDetermineMode determine_mode;
|
|
tSetClock set_clock;
|
|
tGetClock get_clock;
|
|
tHWCursorActive hardware_cursor_active;
|
|
tAcceptsMode accepts_mode;
|
|
tSetupDAC setup_dac;
|
|
tINT10Extensions int10_extensions;
|
|
};
|
|
|
|
extern SVGA_Driver svga;
|
|
extern int enableCGASnow;
|
|
|
|
void SVGA_Setup_S3Trio(void);
|
|
void SVGA_Setup_TsengET4K(void);
|
|
void SVGA_Setup_TsengET3K(void);
|
|
void SVGA_Setup_ParadisePVGA1A(void);
|
|
void SVGA_Setup_Driver(void);
|
|
|
|
// Amount of video memory required for a mode, implemented in int10_modes.cpp
|
|
Bitu VideoModeMemSize(Bitu mode);
|
|
|
|
extern uint32_t ExpandTable[256];
|
|
extern uint32_t FillTable[16];
|
|
extern uint32_t CGA_2_Table[16];
|
|
extern uint32_t CGA_4_Table[256];
|
|
extern uint32_t CGA_4_HiRes_Table[256];
|
|
extern uint32_t CGA_16_Table[256];
|
|
extern uint32_t TXT_Font_Table[16];
|
|
extern uint32_t TXT_FG_Table[16];
|
|
extern uint32_t TXT_BG_Table[16];
|
|
extern uint32_t Expand16Table[4][16];
|
|
extern uint32_t Expand16BigTable[0x10000];
|
|
|
|
void VGA_DAC_UpdateColorPalette();
|
|
|
|
extern uint32_t GFX_Rmask;
|
|
extern unsigned char GFX_Rshift;
|
|
|
|
extern uint32_t GFX_Gmask;
|
|
extern unsigned char GFX_Gshift;
|
|
|
|
extern uint32_t GFX_Bmask;
|
|
extern unsigned char GFX_Bshift;
|
|
|
|
extern uint32_t GFX_Amask;
|
|
extern unsigned char GFX_Ashift;
|
|
|
|
extern unsigned char GFX_bpp;
|
|
|
|
/* current dosplay page (controlled by A4h) */
|
|
extern unsigned char *pc98_pgraph_current_display_page;
|
|
/* current CPU page (controlled by A6h) */
|
|
extern unsigned char *pc98_pgraph_current_cpu_page;
|
|
|
|
/* functions to help cleanup memory map access instead of hardcoding offsets.
|
|
* your C++ compiler should be smart enough to inline these into the body of this function. */
|
|
|
|
/* TODO: Changes to memory layout relative to vga.mem.linear:
|
|
*
|
|
* Text to take 0x00000-0x03FFF instead of 0x00000-0x07FFF.
|
|
*
|
|
* Graphics to start at 0x04000
|
|
*
|
|
* Each bitplane will be 64KB (0x10000) bytes long, and the page flip bit in 0xA6
|
|
* will select which 32KB half within the 64KB block to use, or if another bit is
|
|
* set as documented in Undocumented PC-98, the full 64KB block.
|
|
*
|
|
* The 512KB + 32KB will be reduced slightly to 512KB + 16KB to match the layout.
|
|
*
|
|
* The bitplane layout change will permit emulating an 8 bitplane 256-color mode
|
|
* suggested by Yksoft1 that early PC-9821 systems supported and that the 256-color
|
|
* driver shipped with Windows 3.1 (for PC-98) uses. Based on Windows 3.1 behavior
|
|
* that also means the linear framebuffer at 0xF00000 must also change in planar
|
|
* mode to spread all 8 bits across the planes on write and gather all 8 bits
|
|
* on read. As far as I can tell the Windows 3.1 256-color driver uses planar
|
|
* and EGC functions as it would in 16-color mode, but draws bitmaps using the
|
|
* LFB. The picture is wrong EXCEPT when Windows icons and bitmaps are drawn.
|
|
*
|
|
* 256-color packed mode will be retained as direct LFB mapping from the start of
|
|
* graphics RAM.
|
|
*
|
|
* On a real PC-9821 laptop, contents accessible to the CPU noticeably shift order
|
|
* and position when you switch on/off 256-color packed mode, suggesting that the
|
|
* planar mode is simply reordered memory access in hardware OR that 256-color
|
|
* mode is "chained" (much like 256-color packed mode on IBM VGA hardware) across
|
|
* bitplanes. */
|
|
|
|
#define PC98_VRAM_TEXT_OFFSET ( 0x00000u ) /* 16KB memory (8KB text + 8KB attributes) */
|
|
#define PC98_VRAM_GRAPHICS_OFFSET ( 0x04000u ) /* where graphics memory begins */
|
|
|
|
#define PC98_VRAM_BITPLANE_SIZE ( 0x10000u ) /* one bitplane */
|
|
|
|
#define PC98_VRAM_PAGEFLIP_SIZE ( 0x08000u ) /* add this amount for the second page in 8/16/256-color planar mode */
|
|
#define PC98_VRAM_PAGEFLIP256_SIZE ( 0x40000u ) /* add this amount for the second page in 256-color packed mode */
|
|
|
|
#define PC98_VRAM_256BANK_SIZE ( 0x08000u ) /* window/bank size (256-color packed) */
|
|
|
|
extern uint32_t pc98_pegc_banks[2];
|
|
|
|
static inline unsigned char *pc98_vram_text(void) {
|
|
return vga.mem.linear + PC98_VRAM_TEXT_OFFSET;
|
|
}
|
|
|
|
/* return value is relative to current CPU page or current display page ptr */
|
|
static inline constexpr unsigned int pc98_pgram_bitplane_offset(const unsigned int b) {
|
|
/* WARNING: b is not range checked for performance! Do not call with b >= 8 if memsize = 512KB or b >= 4 if memsize >= 256KB */
|
|
return (b * PC98_VRAM_BITPLANE_SIZE);
|
|
}
|
|
|
|
static inline unsigned char *pc98_vram_256bank_from_window(const unsigned int b) {
|
|
/* WARNING: b is not range checked for performance! Do not call with b >= 2 */
|
|
return vga.mem.linear + PC98_VRAM_GRAPHICS_OFFSET + pc98_pegc_banks[b];
|
|
}
|
|
|
|
#define VRAM98_TEXT ( pc98_vram_text() )
|
|
|
|
#endif
|