diff options
Diffstat (limited to 'src/mame/video/espial.c')
-rw-r--r-- | src/mame/video/espial.c | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/src/mame/video/espial.c b/src/mame/video/espial.c new file mode 100644 index 00000000000..2f89e8f530a --- /dev/null +++ b/src/mame/video/espial.c @@ -0,0 +1,243 @@ +/*************************************************************************** + + video.c + + Functions to emulate the video hardware of the machine. + +***************************************************************************/ + +#include "driver.h" +#include "includes/espial.h" + + +UINT8 *espial_videoram; +UINT8 *espial_colorram; +UINT8 *espial_attributeram; +UINT8 *espial_scrollram; +UINT8 *espial_spriteram_1; +UINT8 *espial_spriteram_2; +UINT8 *espial_spriteram_3; + +static int flipscreen; +static tilemap *bg_tilemap; + + +/*************************************************************************** + + Convert the color PROMs into a more useable format. + + Espial has two 256x4 palette PROMs. + + I don't know for sure how the palette PROMs are connected to the RGB + output, but it's probably the usual: + + bit 3 -- 220 ohm resistor -- BLUE + -- 470 ohm resistor -- BLUE + -- 220 ohm resistor -- GREEN + bit 0 -- 470 ohm resistor -- GREEN + bit 3 -- 1 kohm resistor -- GREEN + -- 220 ohm resistor -- RED + -- 470 ohm resistor -- RED + bit 0 -- 1 kohm resistor -- RED + +***************************************************************************/ +PALETTE_INIT( espial ) +{ + int i; + + + for (i = 0;i < machine->drv->total_colors;i++) + { + int bit0,bit1,bit2,r,g,b; + + + /* red component */ + bit0 = (color_prom[i] >> 0) & 0x01; + bit1 = (color_prom[i] >> 1) & 0x01; + bit2 = (color_prom[i] >> 2) & 0x01; + r = 0x21 * bit0 + 0x47 * bit1 + 0x97 * bit2; + /* green component */ + bit0 = (color_prom[i] >> 3) & 0x01; + bit1 = (color_prom[i + machine->drv->total_colors] >> 0) & 0x01; + bit2 = (color_prom[i + machine->drv->total_colors] >> 1) & 0x01; + g = 0x21 * bit0 + 0x47 * bit1 + 0x97 * bit2; + /* blue component */ + bit0 = 0; + bit1 = (color_prom[i + machine->drv->total_colors] >> 2) & 0x01; + bit2 = (color_prom[i + machine->drv->total_colors] >> 3) & 0x01; + b = 0x21 * bit0 + 0x47 * bit1 + 0x97 * bit2; + + palette_set_color(machine,i,MAKE_RGB(r,g,b)); + } +} + + + +/*************************************************************************** + + Callbacks for the TileMap code + +***************************************************************************/ + +static TILE_GET_INFO( get_tile_info ) +{ + UINT8 code = espial_videoram[tile_index]; + UINT8 col = espial_colorram[tile_index]; + UINT8 attr = espial_attributeram[tile_index]; + SET_TILE_INFO(0, + code | ((attr & 0x03) << 8), + col & 0x3f, + TILE_FLIPYX(attr >> 2)); +} + + + +/************************************* + * + * Video system start + * + *************************************/ + +VIDEO_START( espial ) +{ + bg_tilemap = tilemap_create(get_tile_info,tilemap_scan_rows,TILEMAP_TYPE_PEN,8,8,32,32); + + tilemap_set_scroll_cols(bg_tilemap, 32); +} + +VIDEO_START( netwars ) +{ + /* Net Wars has a tile map that's twice as big as Espial's */ + bg_tilemap = tilemap_create(get_tile_info,tilemap_scan_rows,TILEMAP_TYPE_PEN,8,8,32,64); + + tilemap_set_scroll_cols(bg_tilemap, 32); + tilemap_set_scrolldy(bg_tilemap, 0, 0x100); +} + + +/************************************* + * + * Memory handlers + * + *************************************/ + +WRITE8_HANDLER( espial_videoram_w ) +{ + espial_videoram[offset] = data; + tilemap_mark_tile_dirty(bg_tilemap, offset); +} + + +WRITE8_HANDLER( espial_colorram_w ) +{ + espial_colorram[offset] = data; + tilemap_mark_tile_dirty(bg_tilemap, offset); +} + + +WRITE8_HANDLER( espial_attributeram_w ) +{ + espial_attributeram[offset] = data; + tilemap_mark_tile_dirty(bg_tilemap, offset); +} + + +WRITE8_HANDLER( espial_scrollram_w ) +{ + espial_scrollram[offset] = data; + tilemap_set_scrolly(bg_tilemap, offset, data); +} + + +WRITE8_HANDLER( espial_flipscreen_w ) +{ + flipscreen = data; + + tilemap_set_flip(0, flipscreen ? TILEMAP_FLIPX | TILEMAP_FLIPY : 0); +} + + +/************************************* + * + * Video update + * + *************************************/ + +static void draw_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect) +{ + int offs; + + + /* Note that it is important to draw them exactly in this */ + /* order, to have the correct priorities. */ + for (offs = 0;offs < 16;offs++) + { + int sx,sy,code,color,flipx,flipy; + + + sx = espial_spriteram_1[offs + 16]; + sy = espial_spriteram_2[offs]; + code = espial_spriteram_1[offs] >> 1; + color = espial_spriteram_2[offs + 16]; + flipx = espial_spriteram_3[offs] & 0x04; + flipy = espial_spriteram_3[offs] & 0x08; + + if (flipscreen) + { + flipx = !flipx; + flipy = !flipy; + } + else + { + sy = 240 - sy; + } + + if (espial_spriteram_1[offs] & 1) /* double height */ + { + if (flipscreen) + { + drawgfx(bitmap,machine->gfx[1], + code,color, + flipx,flipy, + sx,sy + 16, + cliprect,TRANSPARENCY_PEN,0); + drawgfx(bitmap,machine->gfx[1], + code + 1, + color, + flipx,flipy, + sx,sy, + cliprect,TRANSPARENCY_PEN,0); + } + else + { + drawgfx(bitmap,machine->gfx[1], + code,color, + flipx,flipy, + sx,sy - 16, + cliprect,TRANSPARENCY_PEN,0); + drawgfx(bitmap,machine->gfx[1], + code + 1,color, + flipx,flipy, + sx,sy, + cliprect,TRANSPARENCY_PEN,0); + } + } + else + { + drawgfx(bitmap,machine->gfx[1], + code,color, + flipx,flipy, + sx,sy, + cliprect,TRANSPARENCY_PEN,0); + } + } +} + + +VIDEO_UPDATE( espial ) +{ + tilemap_draw(bitmap,cliprect,bg_tilemap,0,0); + + draw_sprites(machine, bitmap, cliprect); + return 0; +} |