Mercurial > repos > blastem
view jag_video.c @ 1089:87597a048d38
Initial implementation of video output hardware
author | Michael Pavone <pavone@retrodev.com> |
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date | Wed, 12 Oct 2016 09:39:52 -0700 |
parents | c0a026e974f4 |
children | a68274a25e2f |
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#include <stdint.h> #include <stdlib.h> #include <stdio.h> #include "jag_video.h" #include "render.h" enum { VMODE_CRY, VMODE_RGB24, VMODE_DIRECT16, VMODE_RGB16, VMODE_VARIABLE }; #define BIT_TBGEN 1 char *vmode_names[] = { "CRY", "RGB24", "RGB16", "DIRECT16", "VARIABLE" }; static uint8_t cry_red[9][16] = { {0, 34, 68, 102, 135, 169, 203, 237, 255, 255, 255, 255, 255, 255, 255, 255}, {0, 34, 68, 102, 135, 169, 203, 230, 247, 255, 255, 255, 255, 255, 255, 255}, {0, 34, 68, 102, 135, 170, 183, 197, 214, 235, 255, 255, 255, 255, 255, 255}, {0, 34, 68, 102, 130, 141, 153, 164, 181, 204, 227, 249, 255, 255, 255, 255}, {0, 34, 68, 95, 104, 113, 122, 131, 148, 173, 198, 223, 248, 255, 255, 255}, {0, 34, 64, 71, 78, 85, 91, 98, 115, 143, 170, 197, 224, 252, 255, 255}, {0, 34, 43, 47, 52, 56, 61, 65, 82, 112, 141, 171, 200, 230, 255, 255}, {0, 19, 21, 23, 26, 28, 30, 32, 49, 81, 113, 145, 177, 208, 240, 255}, {0, 0, 0, 0, 0, 0, 0, 0, 17, 51, 85, 119, 153, 187, 221, 255} }; static uint8_t cry_green[16][8] = { {0, 0, 0, 0, 0, 0, 0, 0}, {17, 19, 21, 23, 26, 28, 30, 32}, {34, 38, 43, 47, 52, 56, 61, 65}, {51, 57, 64, 71, 78, 85, 91, 98}, {68, 77, 86, 95, 104, 113, 122, 131}, {85, 96, 107, 119, 130, 141, 153, 164}, {102, 115, 129, 142, 156, 170, 183, 197}, {119, 134, 150, 166, 182, 198, 214, 230}, {136, 154, 172, 190, 208, 226, 244, 255}, {153, 173, 193, 214, 234, 255, 255, 255}, {170, 192, 215, 238, 255, 255, 255, 255}, {187, 211, 236, 255, 255, 255, 255, 255}, {204, 231, 255, 255, 255, 255, 255, 255}, {221, 250, 255, 255, 255, 255, 255, 255}, {238, 255, 255, 255, 255, 255, 255, 255}, {255, 255, 255, 255, 255, 255, 255, 255}, }; static uint32_t table_cry[0x10000]; static uint32_t table_rgb[0x10000]; static uint32_t table_variable[0x10000]; static uint32_t cry_to_rgb(uint16_t cry) { uint32_t y = cry & 0xFF; if (y) { uint8_t c = cry >> 12; uint8_t r = cry >> 8 & 0xF; uint32_t red = cry_red[c < 7 ? 0 : c - 7][r]; uint32_t green = cry_green[c][r < 8 ? r : 15 - r]; uint32_t blue = cry_red[c < 7 ? 0 : c - 7][15-r]; red = red * 255 / y; blue = blue * 255 / y; green = green * 255 / y; return render_map_color(red, green, blue); } else { return render_map_color(0, 0, 0); } } static uint32_t rgb16_to_rgb(uint16_t rgb) { return render_map_color( rgb >> 8 & 0xF8, rgb << 2 & 0xFC, rgb >> 4 & 0xF8 ); } jag_video *jag_video_init(void) { static uint8_t table_init_done = 0; if (!table_init_done) { for (int i = 0; i < 0x10000; i++) { table_cry[i] = cry_to_rgb(i); table_rgb[i] = rgb16_to_rgb(i); table_variable[i] = i & 1 ? rgb16_to_rgb(i & 0xFFFE) : cry_to_rgb(i); } table_init_done = 1; } return calloc(1, sizeof(jag_video)); } static void copy_16(uint32_t *dst, uint32_t len, uint16_t *linebuffer, uint32_t *table) { for (; len; len--, dst++, linebuffer++) { *dst = table[*linebuffer]; } } static void copy_linebuffer(jag_video *context, uint16_t *linebuffer) { if (!context->output) { return; } uint32_t *dst = context->output; uint32_t len; if (context->regs[VID_HCOUNT] == context->regs[VID_HDISP_BEGIN1]) { if ( context->regs[VID_HDISP_BEGIN2] == context->regs[VID_HDISP_BEGIN1] || context->regs[VID_HDISP_BEGIN2] > (context->regs[VID_HPERIOD] | 0x400) ) { //only one line buffer per line, so copy the previous line in its entirety len = context->regs[VID_HDISP_END] - 0x400 + context->regs[VID_HPERIOD] - context->regs[VID_HDISP_BEGIN1] + 2; } else { //copy the second half of the previous line if (context->regs[VID_HDISP_BEGIN2] & 0x400) { //BEGIN2 is after the HCOUNT jump dst += context->regs[VID_HPERIOD] - context->regs[VID_HDISP_BEGIN1] + context->regs[VID_HDISP_BEGIN2] - 0x400 + 1; len = context->regs[VID_HDISP_END] - context->regs[VID_HDISP_BEGIN2] + 1; } else { //BEGIN2 is before the HCOUNT jump dst += context->regs[VID_HDISP_BEGIN2] - context->regs[VID_HDISP_BEGIN1]; len = context->regs[VID_HDISP_END] + context->regs[VID_HPERIOD] - context->regs[VID_HDISP_BEGIN2] + 2; } } context->output += context->output_pitch / sizeof(uint32_t); } else { //copy the first half of the current line if (context->regs[VID_HDISP_BEGIN2] & 0x400) { //BEGIN2 is after the HCOUNT jump len = context->regs[VID_HDISP_BEGIN2] - 0x400 + context->regs[VID_HPERIOD] - context->regs[VID_HDISP_BEGIN1] + 1; } else { //BEGIN2 is before the HCOUNT jump len = context->regs[VID_HDISP_BEGIN2] - context->regs[VID_HDISP_BEGIN1]; } } len /= context->pclock_div; switch (context->mode) { case VMODE_CRY: copy_16(dst, len, linebuffer, table_cry); break; case VMODE_RGB24: //TODO: Implement me break; case VMODE_DIRECT16: //TODO: Implement this once I better understand what would happen on hardware with composite output break; case VMODE_RGB16: copy_16(dst, len, linebuffer, table_rgb); break; case VMODE_VARIABLE: copy_16(dst, len, linebuffer, table_variable); break; } } void jag_video_run(jag_video *context, uint32_t target_cycle) { if (context->regs[VID_VMODE] & BIT_TBGEN) { while (context->cycles < target_cycle) { //TODO: Optimize this to not actually increment one step at a time if ( ( context->regs[VID_HCOUNT] == context->regs[VID_HDISP_BEGIN1] || context->regs[VID_HCOUNT] == context->regs[VID_HDISP_BEGIN2] ) && context->regs[VID_VCOUNT] >= context->regs[VID_VDISP_BEGIN] && context->regs[VID_VCOUNT] < context->regs[VID_VDISP_END] ) { //swap linebuffers, render linebuffer to framebuffer and kick off object processor if (context->write_line_buffer == context->line_buffer_a) { context->write_line_buffer = context->line_buffer_b; copy_linebuffer(context, context->line_buffer_a); } else { context->write_line_buffer = context->line_buffer_a; copy_linebuffer(context, context->line_buffer_b); } //clear new write line buffer with background color for (int i = 0; i < LINEBUFFER_WORDS; i++) { context->write_line_buffer[i] = context->regs[VID_BGCOLOR]; } //TODO: kick off object processor } if ( !context->output && context->regs[VID_VCOUNT] == context->regs[VID_VDISP_BEGIN] && context->regs[VID_HCOUNT] == context->regs[VID_HDISP_BEGIN1] ) { context->output = render_get_framebuffer(FRAMEBUFFER_ODD, &context->output_pitch); } else if (context->output && context->regs[VID_VCOUNT] >= context->regs[VID_VDISP_END]) { int width = (context->regs[VID_HPERIOD] - context->regs[VID_HDISP_BEGIN1] + context->regs[VID_HDISP_END] - 1024 + 2) / context->pclock_div; render_framebuffer_updated(FRAMEBUFFER_ODD, width); context->output = NULL; } if ((context->regs[VID_HCOUNT] & 0x3FF) == context->regs[VID_HPERIOD]) { //reset bottom 10 bits to zero, flip the 11th bit which represents which half of the line we're on context->regs[VID_HCOUNT] = (context->regs[VID_HCOUNT] & 0x400) ^ 0x400; //increment half-line counter if (context->regs[VID_VCOUNT] == context->regs[VID_VPERIOD]) { context->regs[VID_VCOUNT] = 0; } else { context->regs[VID_VCOUNT]++; } } else { context->regs[VID_HCOUNT]++; } context->cycles++; } } else { context->cycles = target_cycle; } } static uint8_t is_reg_writeable(uint32_t address) { return address < VID_HLPEN || address >= VID_OBJLIST1; } void jag_video_reg_write(jag_video *context, uint32_t address, uint16_t value) { uint32_t reg = (address >> 1 & 0x7F) - 2; if (reg < JAG_VIDEO_REGS && is_reg_writeable(reg)) { context->regs[reg] = value; if (reg == VID_VMODE) { context->pclock_div = (value >> 9 & 7) + 1; context->pclock_counter = 0; if (value & 0x10) { context->mode = VMODE_VARIABLE; } else { context->mode = value >> 1 & 3; } printf("Mode %s, pixel clock divider: %d, time base generation: %s\n", vmode_names[context->mode], context->pclock_div, value & BIT_TBGEN ? "enabled" : "disabled"); } switch (reg) { case VID_OBJLIST1: printf("Object List Pointer 1: %X\n", value); break; case VID_OBJLIST2: printf("Object List Pointer 2: %X\n", value); break; case VID_HPERIOD: printf("Horizontal period: %d\n", value & 0x3FF); break; case VID_HBLANK_BEGIN: printf("horizontal blanking begin: %d\n", value & 0x7FF); break; case VID_HBLANK_END: printf("horizontal blanking end: %d\n", value & 0x7FF); break; case VID_HSYNC: printf("horizontal sync start: %d\n", value & 0x7FF); break; case VID_HDISP_BEGIN1: printf("horizontal display begin 1: %d\n", value & 0x7FF); break; case VID_HDISP_BEGIN2: printf("horizontal display begin 2: %d\n", value & 0x7FF); break; case VID_HDISP_END: printf("horizontal display end: %d\n", value & 0x7FF); break; case VID_VPERIOD: printf("Vertical period: %d\n", value & 0x7FF); break; case VID_VBLANK_BEGIN: printf("vertical blanking begin: %d\n", value & 0x7FF); break; case VID_VBLANK_END: printf("vertical blanking end: %d\n", value & 0x7FF); break; case VID_VSYNC: printf("vertical sync start: %d\n", value & 0x7FF); break; case VID_VDISP_BEGIN: printf("vertical display begin: %d\n", value & 0x7FF); break; case VID_VDISP_END: printf("vertical display end: %d\n", value & 0x7FF); break; } } else { fprintf(stderr, "Write to invalid video/object processor register %X:%X\n", address, value); } }