/************************************************************************* BattleToads Video hardware emulation **************************************************************************/ #include "driver.h" #include "cpu/tms34010/tms34010.h" #include "video/tlc34076.h" #include "btoads.h" #define BT_DEBUG 0 /************************************* * * Global variables * *************************************/ UINT16 *btoads_vram_fg0, *btoads_vram_fg1, *btoads_vram_fg_data; UINT16 *btoads_vram_bg0, *btoads_vram_bg1; UINT16 *btoads_sprite_scale; UINT16 *btoads_sprite_control; static UINT8 *vram_fg_draw, *vram_fg_display; static INT32 xscroll0, yscroll0; static INT32 xscroll1, yscroll1; static UINT8 screen_control; static UINT16 sprite_source_offs; static UINT8 *sprite_dest_base; static UINT16 sprite_dest_offs; static UINT16 misc_control; /************************************* * * Video system start * *************************************/ VIDEO_START( btoads ) { /* initialize the swapped pointers */ vram_fg_draw = (UINT8 *)btoads_vram_fg0; vram_fg_display = (UINT8 *)btoads_vram_fg1; state_save_register_global(xscroll0); state_save_register_global(xscroll1); state_save_register_global(yscroll0); state_save_register_global(yscroll1); state_save_register_global(screen_control); state_save_register_global(sprite_source_offs); state_save_register_global(sprite_dest_offs); state_save_register_global(misc_control); } /************************************* * * Control registers * *************************************/ WRITE16_HANDLER( btoads_misc_control_w ) { COMBINE_DATA(&misc_control); /* bit 3 controls sound reset line */ cpunum_set_input_line(1, INPUT_LINE_RESET, (misc_control & 8) ? CLEAR_LINE : ASSERT_LINE); } WRITE16_HANDLER( btoads_display_control_w ) { if (ACCESSING_MSB) { /* allow multiple changes during display */ video_screen_update_partial(0, video_screen_get_vpos(0) - 1); /* bit 15 controls which page is rendered and which page is displayed */ if (data & 0x8000) { vram_fg_draw = (UINT8 *)btoads_vram_fg1; vram_fg_display = (UINT8 *)btoads_vram_fg0; } else { vram_fg_draw = (UINT8 *)btoads_vram_fg0; vram_fg_display = (UINT8 *)btoads_vram_fg1; } /* stash the remaining data for later */ screen_control = data >> 8; } } /************************************* * * Scroll registers * *************************************/ WRITE16_HANDLER( btoads_scroll0_w ) { /* allow multiple changes during display */ video_screen_update_partial(0, video_screen_get_vpos(0) - 1); /* upper bits are Y scroll, lower bits are X scroll */ if (ACCESSING_MSB) yscroll0 = data >> 8; if (ACCESSING_LSB) xscroll0 = data & 0xff; } WRITE16_HANDLER( btoads_scroll1_w ) { /* allow multiple changes during display */ video_screen_update_partial(0, video_screen_get_vpos(0) - 1); /* upper bits are Y scroll, lower bits are X scroll */ if (ACCESSING_MSB) yscroll1 = data >> 8; if (ACCESSING_LSB) xscroll1 = data & 0xff; } /************************************* * * Palette RAM * *************************************/ WRITE16_HANDLER( btoads_paletteram_w ) { tlc34076_lsb_w(offset/2, data, mem_mask); } READ16_HANDLER( btoads_paletteram_r ) { return tlc34076_lsb_r(offset/2, mem_mask); } /************************************* * * Background video RAM * *************************************/ WRITE16_HANDLER( btoads_vram_bg0_w ) { COMBINE_DATA(&btoads_vram_bg0[offset & 0x3fcff]); } WRITE16_HANDLER( btoads_vram_bg1_w ) { COMBINE_DATA(&btoads_vram_bg1[offset & 0x3fcff]); } READ16_HANDLER( btoads_vram_bg0_r ) { return btoads_vram_bg0[offset & 0x3fcff]; } READ16_HANDLER( btoads_vram_bg1_r ) { return btoads_vram_bg1[offset & 0x3fcff]; } /************************************* * * Foreground video RAM * *************************************/ WRITE16_HANDLER( btoads_vram_fg_display_w ) { if (ACCESSING_LSB) vram_fg_display[offset] = data; } WRITE16_HANDLER( btoads_vram_fg_draw_w ) { if (ACCESSING_LSB) vram_fg_draw[offset] = data; } READ16_HANDLER( btoads_vram_fg_display_r ) { return vram_fg_display[offset]; } READ16_HANDLER( btoads_vram_fg_draw_r ) { return vram_fg_draw[offset]; } /************************************* * * Sprite rendering * *************************************/ static void render_sprite_row(UINT16 *sprite_source, UINT32 address) { int flipxor = ((*btoads_sprite_control >> 10) & 1) ? 0xffff : 0x0000; int width = (~*btoads_sprite_control & 0x1ff) + 2; int color = (~*btoads_sprite_control >> 8) & 0xf0; int srcoffs = sprite_source_offs << 8; int srcend = srcoffs + (width << 8); int srcstep = 0x100 - btoads_sprite_scale[0]; int dststep = 0x100 - btoads_sprite_scale[8]; int dstoffs = sprite_dest_offs << 8; /* non-shadow case */ if (!(misc_control & 0x10)) { for ( ; srcoffs < srcend; srcoffs += srcstep, dstoffs += dststep) { UINT16 src = sprite_source[(srcoffs >> 10) & 0x1ff]; if (src) { src = (src >> (((srcoffs ^ flipxor) >> 6) & 0x0c)) & 0x0f; if (src) sprite_dest_base[(dstoffs >> 8) & 0x1ff] = src | color; } } } /* shadow case */ else { for ( ; srcoffs < srcend; srcoffs += srcstep, dstoffs += dststep) { UINT16 src = sprite_source[(srcoffs >> 10) & 0x1ff]; if (src) { src = (src >> (((srcoffs ^ flipxor) >> 6) & 0x0c)) & 0x0f; if (src) sprite_dest_base[(dstoffs >> 8) & 0x1ff] = color; } } } sprite_source_offs += width; sprite_dest_offs = dstoffs >> 8; } /************************************* * * Shift register read/write * *************************************/ void btoads_to_shiftreg(UINT32 address, UINT16 *shiftreg) { address &= ~0x40000000; /* reads from this first region are usual shift register reads */ if (address >= 0xa0000000 && address <= 0xa3ffffff) memcpy(shiftreg, &vram_fg_display[TOWORD(address & 0x3fffff)], TOBYTE(0x1000)); /* reads from this region set the sprite destination address */ else if (address >= 0xa4000000 && address <= 0xa7ffffff) { sprite_dest_base = &vram_fg_draw[TOWORD(address & 0x3fc000)]; sprite_dest_offs = (INT16)((address & 0x3ff) << 2) >> 2; } /* reads from this region set the sprite source address */ else if (address >= 0xa8000000 && address <= 0xabffffff) { memcpy(shiftreg, &btoads_vram_fg_data[TOWORD(address & 0x7fc000)], TOBYTE(0x2000)); sprite_source_offs = (address & 0x003fff) >> 3; } else logerror("%08X:btoads_to_shiftreg(%08X)\n", activecpu_get_pc(), address); } void btoads_from_shiftreg(UINT32 address, UINT16 *shiftreg) { address &= ~0x40000000; /* writes to this first region are usual shift register writes */ if (address >= 0xa0000000 && address <= 0xa3ffffff) memcpy(&vram_fg_display[TOWORD(address & 0x3fc000)], shiftreg, TOBYTE(0x1000)); /* writes to this region are ignored for our purposes */ else if (address >= 0xa4000000 && address <= 0xa7ffffff) ; /* writes to this region copy standard data */ else if (address >= 0xa8000000 && address <= 0xabffffff) memcpy(&btoads_vram_fg_data[TOWORD(address & 0x7fc000)], shiftreg, TOBYTE(0x2000)); /* writes to this region render the current sprite data */ else if (address >= 0xac000000 && address <= 0xafffffff) render_sprite_row(shiftreg, address); else logerror("%08X:btoads_from_shiftreg(%08X)\n", activecpu_get_pc(), address); } /************************************* * * Main refresh * *************************************/ void btoads_scanline_update(running_machine *machine, int screen, mame_bitmap *bitmap, int scanline, const tms34010_display_params *params) { UINT32 fulladdr = ((params->rowaddr << 16) | params->coladdr) >> 4; UINT16 *bg0_base = &btoads_vram_bg0[(fulladdr + (yscroll0 << 10)) & 0x3fc00]; UINT16 *bg1_base = &btoads_vram_bg1[(fulladdr + (yscroll1 << 10)) & 0x3fc00]; UINT8 *spr_base = &vram_fg_display[fulladdr & 0x3fc00]; UINT16 *dst = BITMAP_ADDR16(bitmap, scanline, 0); int coladdr = fulladdr & 0x3ff; int x; if (BT_DEBUG) popmessage("screen_control = %02X", screen_control); /* for each scanline, switch off the render mode */ switch (screen_control & 3) { /* mode 0: used in ship level, snake boss, title screen (free play) */ /* priority is: 1. BG1 pixels with the high bit set 2. Sprites 3. BG1 4. BG0 */ case 0: for (x = params->heblnk; x < params->hsblnk; x += 2, coladdr++) { UINT16 bg0pix = bg0_base[(coladdr + xscroll0) & 0xff]; UINT16 bg1pix = bg1_base[(coladdr + xscroll1) & 0xff]; UINT8 sprpix = spr_base[coladdr & 0xff]; if (bg1pix & 0x80) dst[x + 0] = bg1pix & 0xff; else if (sprpix) dst[x + 0] = sprpix; else if (bg1pix & 0xff) dst[x + 0] = bg1pix & 0xff; else dst[x + 0] = bg0pix & 0xff; if (bg1pix & 0x8000) dst[x + 1] = bg1pix >> 8; else if (sprpix) dst[x + 1] = sprpix; else if (bg1pix >> 8) dst[x + 1] = bg1pix >> 8; else dst[x + 1] = bg0pix >> 8; } break; /* mode 1: used in snow level, title screen (free play), top part of rolling ball level */ /* priority is: 1. Sprite pixels with high bit clear 2. BG0 3. BG1 pixels with high bit set 4. Sprite pixels with high bit set 5. BG1 */ case 1: for (x = params->heblnk; x < params->hsblnk; x += 2, coladdr++) { UINT8 sprpix = spr_base[coladdr & 0xff]; if (sprpix && !(sprpix & 0x80)) { dst[x + 0] = sprpix; dst[x + 1] = sprpix; } else { UINT16 bg0pix = bg0_base[(coladdr + xscroll0) & 0xff]; UINT16 bg1pix = bg1_base[(coladdr + xscroll1) & 0xff]; if (bg0pix & 0xff) dst[x + 0] = bg0pix & 0xff; else if (bg1pix & 0x80) dst[x + 0] = bg1pix & 0xff; else if (sprpix) dst[x + 0] = sprpix; else dst[x + 0] = bg1pix & 0xff; if (bg0pix >> 8) dst[x + 1] = bg0pix >> 8; else if (bg1pix & 0x8000) dst[x + 1] = bg1pix >> 8; else if (sprpix) dst[x + 1] = sprpix; else dst[x + 1] = bg1pix >> 8; } } break; /* mode 2: used in EOA screen, jetpack level, first level, high score screen */ /* priority is: 1. Sprites 2. BG1 3. BG0 */ case 2: for (x = params->heblnk; x < params->hsblnk; x += 2, coladdr++) { UINT8 sprpix = spr_base[coladdr & 0xff]; if (sprpix) { dst[x + 0] = sprpix; dst[x + 1] = sprpix; } else { UINT16 bg0pix = bg0_base[(coladdr + xscroll0) & 0xff]; UINT16 bg1pix = bg1_base[(coladdr + xscroll1) & 0xff]; if (bg1pix & 0xff) dst[x + 0] = bg1pix & 0xff; else dst[x + 0] = bg0pix & 0xff; if (bg1pix >> 8) dst[x + 1] = bg1pix >> 8; else dst[x + 1] = bg0pix >> 8; } } break; /* mode 3: used in toilet level, toad intros, bottom of rolling ball level */ /* priority is: 1. BG1 pixels with the high bit set 2. Sprite pixels with the high bit set 3. BG1 4. Sprites 5. BG0 */ case 3: for (x = params->heblnk; x < params->hsblnk; x += 2, coladdr++) { UINT16 bg0pix = bg0_base[(coladdr + xscroll0) & 0xff]; UINT16 bg1pix = bg1_base[(coladdr + xscroll1) & 0xff]; UINT8 sprpix = spr_base[coladdr & 0xff]; if (bg1pix & 0x80) dst[x + 0] = bg1pix & 0xff; else if (sprpix & 0x80) dst[x + 0] = sprpix; else if (bg1pix & 0xff) dst[x + 0] = bg1pix & 0xff; else if (sprpix) dst[x + 0] = sprpix; else dst[x + 0] = bg0pix & 0xff; if (bg1pix & 0x8000) dst[x + 1] = bg1pix >> 8; else if (sprpix & 0x80) dst[x + 1] = sprpix; else if (bg1pix >> 8) dst[x + 1] = bg1pix >> 8; else if (sprpix) dst[x + 1] = sprpix; else dst[x + 1] = bg0pix >> 8; } break; } /* debugging - dump the screen contents to a file */ #if BT_DEBUG if (input_code_pressed(KEYCODE_X)) { static int count = 0; char name[10]; FILE *f; int i; sprintf(name, "disp%d.log", count++); f = fopen(name, "w"); fprintf(f, "screen_control = %04X\n\n", screen_control << 8); for (i = 0; i < 3; i++) { UINT16 *base = (i == 0) ? (UINT16 *)vram_fg_display : (i == 1) ? btoads_vram_bg0 : btoads_vram_bg1; int xscr = (i == 0) ? 0 : (i == 1) ? xscroll0 : xscroll1; int yscr = (i == 0) ? 0 : (i == 1) ? yscroll0 : yscroll1; int y; for (y = 0; y < 224; y++) { UINT32 offs = ((y + yscr) & 0xff) * TOWORD(0x4000); for (x = 0; x < 256; x++) { UINT16 pix = base[offs + ((x + xscr) & 0xff)]; fprintf(f, "%02X%02X", pix & 0xff, pix >> 8); if (x % 16 == 15) fprintf(f, " "); } fprintf(f, "\n"); } fprintf(f, "\n\n"); } fclose(f); } logerror("---VBLANK---\n"); #endif }