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Diffstat (limited to 'src/mame/video/espial.c')
-rw-r--r--src/mame/video/espial.c243
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;
+}