// license:BSD-3-Clause // copyright-holders:Bryan McPhail, David Graves #include "emu.h" #include "includes/groundfx.h" #include "screen.h" /******************************************************************/ void groundfx_state::video_start() { m_spritelist = std::make_unique(0x4000); /* Hack */ m_hack_cliprect.set(69, 250, 24 + 5, 24 + 44); } /*************************************************************** SPRITE DRAW ROUTINES We draw a series of small tiles ("chunks") together to create each big sprite. The spritemap rom provides the lookup table for this. The game hardware looks up 16x16 sprite chunks from the spritemap rom, creating a 64x64 sprite like this: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 (where the number is the word offset into the spritemap rom). It can also create 32x32 sprites. NB: unused portions of the spritemap rom contain hex FF's. It is a useful coding check to warn in the log if these are being accessed. [They can be inadvertently while spriteram is being tested, take no notice of that.] Heavy use is made of sprite zooming. *** Sprite table layout (4 long words per entry) ------------------------------------------ 0 | ........ x....... ........ ........ | Flip X 0 | ........ .xxxxxxx ........ ........ | ZoomX 0 | ........ ........ .xxxxxxx xxxxxxxx | Sprite Tile | | 2 | ........ ....xx.. ........ ........ | Sprite/tile priority [*] 2 | ........ ......xx xxxxxx.. ........ | Palette bank 2 | ........ ........ ......xx xxxxxxxx | X position | | 3 | ........ .....x.. ........ ........ | Sprite size (0=32x32, 1=64x64) 3 | ........ ......x. ........ ........ | Flip Y 3 | ........ .......x xxxxxx.. ........ | ZoomY 3 | ........ ........ ......xx xxxxxxxx | Y position ------------------------------------------ [* 00=over BG0, 01=BG1, 10=BG2, 11=BG3 ] [or 00=over BG1, 01=BG2, 10=BG3, 11=BG3 ] ***************************************************************/ void groundfx_state::draw_sprites(screen_device &screen, bitmap_ind16 &bitmap,const rectangle &cliprect,int do_hack,int x_offs,int y_offs) { int sprites_flipscreen = 0; static const u32 primasks[4] = {0xffff, 0xfffc, 0xfff0, 0xff00 }; /* pdrawgfx() needs us to draw sprites front to back, so we have to build a list while processing sprite ram and then draw them all at the end */ struct gfx_tempsprite *sprite_ptr = m_spritelist.get(); for (int offs = (m_spriteram.bytes() / 4 - 4); offs >= 0; offs -= 4) { u32 data = m_spriteram[offs+0]; int flipx = (data & 0x00800000) >> 23; int zoomx = (data & 0x007f0000) >> 16; const u32 tilenum = (data & 0x00007fff); data = m_spriteram[offs+2]; const int priority = (data & 0x000c0000) >> 18; u32 color = (data & 0x0003fc00) >> 10; int x = (data & 0x000003ff); data = m_spriteram[offs+3]; const int dblsize = (data & 0x00040000) >> 18; int flipy = (data & 0x00020000) >> 17; int zoomy = (data & 0x0001fc00) >> 10; int y = (data & 0x000003ff); // color |= (0x100 + (priority << 6)); /* priority bits select color bank */ color /= 2; /* as sprites are 5bpp */ flipy = !flipy; y = (-y & 0x3ff); if (!tilenum) continue; flipy = !flipy; zoomx += 1; zoomy += 1; y += y_offs; /* treat coords as signed */ if (x>0x340) x -= 0x400; if (y>0x340) y -= 0x400; x -= x_offs; const int dimension = ((dblsize*2) + 2); // 2 or 4 const int total_chunks = ((dblsize*3) + 1) << 2; // 4 or 16 const int map_offset = tilenum << 2; { for (int sprite_chunk = 0; sprite_chunk < total_chunks; sprite_chunk++) { const int j = sprite_chunk / dimension; /* rows */ const int k = sprite_chunk % dimension; /* chunks per row */ int px = k; int py = j; /* pick tiles back to front for x and y flips */ if (flipx) px = dimension-1-k; if (flipy) py = dimension-1-j; const u16 code = m_spritemap[map_offset + px + (py << (dblsize + 1))]; if (code==0xffff) { continue; } int curx = x + ((k * zoomx) / dimension); int cury = y + ((j * zoomy) / dimension); const int zx = x + (((k + 1) * zoomx) / dimension) - curx; const int zy = y + (((j + 1) * zoomy) / dimension) - cury; if (sprites_flipscreen) { /* -zx/y is there to fix zoomed sprite coords in screenflip. drawgfxzoom does not know to draw from flip-side of sprites when screen is flipped; so we must correct the coords ourselves. */ curx = 320 - curx - zx; cury = 256 - cury - zy; flipx = !flipx; flipy = !flipy; } sprite_ptr->gfx = 0; sprite_ptr->code = code; sprite_ptr->color = color; sprite_ptr->flipx = !flipx; sprite_ptr->flipy = flipy; sprite_ptr->x = curx; sprite_ptr->y = cury; sprite_ptr->zoomx = zx << 12; sprite_ptr->zoomy = zy << 12; sprite_ptr->pri = priority; sprite_ptr++; } } } /* this happens only if primsks != nullptr */ while (sprite_ptr != m_spritelist.get()) { const rectangle *clipper; sprite_ptr--; if (do_hack && sprite_ptr->pri == 1 && sprite_ptr->y < 100) clipper = &m_hack_cliprect; else clipper = &cliprect; m_gfxdecode->gfx(sprite_ptr->gfx)->prio_zoom_transpen(bitmap,*clipper, sprite_ptr->code, sprite_ptr->color, sprite_ptr->flipx,sprite_ptr->flipy, sprite_ptr->x,sprite_ptr->y, sprite_ptr->zoomx,sprite_ptr->zoomy, screen.priority(),primasks[sprite_ptr->pri],0); } } /************************************************************** SCREEN REFRESH **************************************************************/ u32 groundfx_state::screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect) { u8 layer[5]; u8 scclayer[3]; m_tc0620scc->tilemap_update(); m_tc0480scp->tilemap_update(); const u16 priority = m_tc0480scp->get_bg_priority(); layer[0] = (priority & 0xf000) >> 12; /* tells us which bg layer is bottom */ layer[1] = (priority & 0x0f00) >> 8; layer[2] = (priority & 0x00f0) >> 4; layer[3] = (priority & 0x000f) >> 0; /* tells us which is top */ layer[4] = 4; /* text layer always over bg layers */ scclayer[0] = m_tc0620scc->bottomlayer(); scclayer[1] = scclayer[0]^1; scclayer[2] = 2; screen.priority().fill(0, cliprect); bitmap.fill(0, cliprect); /* wrong color? */ m_tc0620scc->tilemap_draw(screen, bitmap, cliprect, scclayer[0], TILEMAP_DRAW_OPAQUE, 0); m_tc0620scc->tilemap_draw(screen, bitmap, cliprect, scclayer[1], 0, 0); /* BIG HACK! The rear view mirror is a big priority trick - the text layer of TC0100SCN is used as a stencil to display the bottom layer of TC0480SCP and a particular sprite priority. These never appear outside of the stencil. I'm not sure how the game turns this effect on/off (the 480 layer is used normally in the frontend of the game). I haven't implemented it properly yet, instead I'm doing a hacky cliprect around the rearview and drawing it's contents the usual way. */ if (m_tc0620scc->ram_r(0x4090 / 2) || m_tc0620scc->ram_r(0x4092 / 2) || ((m_tc0480scp->ram_r(0x20 / 2) == 0x24) && (m_tc0480scp->ram_r(0x22 / 2) == 0x0866))) /* Anything in text layer - really stupid hack */ { m_tc0480scp->tilemap_draw(screen, bitmap, cliprect, layer[1], 0, 2); m_tc0480scp->tilemap_draw(screen, bitmap, cliprect, layer[2], 0, 4); m_tc0480scp->tilemap_draw(screen, bitmap, cliprect, layer[3], 0, 8); //m_tc0620scc->tilemap_draw(screen, bitmap, cliprect, 0, scclayer[2], 0, 0); if ((m_tc0480scp->ram_r(0x20 / 2) != 0x24) && (m_tc0480scp->ram_r(0x22 / 2) != 0x0866)) /* Stupid hack for start of race */ m_tc0480scp->tilemap_draw(screen, bitmap, m_hack_cliprect, layer[0], 0, 0); draw_sprites(screen, bitmap, cliprect, 1, 44, -574); } else { m_tc0480scp->tilemap_draw(screen, bitmap, cliprect, layer[0], 0, 1); m_tc0480scp->tilemap_draw(screen, bitmap, cliprect, layer[1], 0, 2); m_tc0480scp->tilemap_draw(screen, bitmap, cliprect, layer[2], 0, 4); m_tc0480scp->tilemap_draw(screen, bitmap, cliprect, layer[3], 0, 8); m_tc0620scc->tilemap_draw(screen, bitmap, cliprect, scclayer[2], 0, 0); draw_sprites(screen, bitmap, cliprect, 0, 44, -574); } m_tc0480scp->tilemap_draw(screen, bitmap, cliprect, layer[4], 0, 0); /* TC0480SCP text layer */ return 0; }