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Diffstat (limited to 'src/mame/video/pbaction.c')
-rw-r--r--src/mame/video/pbaction.c134
1 files changed, 134 insertions, 0 deletions
diff --git a/src/mame/video/pbaction.c b/src/mame/video/pbaction.c
new file mode 100644
index 00000000000..ec68041a988
--- /dev/null
+++ b/src/mame/video/pbaction.c
@@ -0,0 +1,134 @@
+/***************************************************************************
+
+ video.c
+
+ Functions to emulate the video hardware of the machine.
+
+***************************************************************************/
+
+#include "driver.h"
+
+UINT8 *pbaction_videoram2, *pbaction_colorram2;
+
+static int scroll;
+
+static tilemap *bg_tilemap, *fg_tilemap;
+
+WRITE8_HANDLER( pbaction_videoram_w )
+{
+ videoram[offset] = data;
+ tilemap_mark_tile_dirty(bg_tilemap, offset);
+}
+
+WRITE8_HANDLER( pbaction_colorram_w )
+{
+ colorram[offset] = data;
+ tilemap_mark_tile_dirty(bg_tilemap, offset);
+}
+
+WRITE8_HANDLER( pbaction_videoram2_w )
+{
+ pbaction_videoram2[offset] = data;
+ tilemap_mark_tile_dirty(fg_tilemap, offset);
+}
+
+WRITE8_HANDLER( pbaction_colorram2_w )
+{
+ pbaction_colorram2[offset] = data;
+ tilemap_mark_tile_dirty(fg_tilemap, offset);
+}
+
+WRITE8_HANDLER( pbaction_scroll_w )
+{
+ scroll = data - 3;
+ if (flip_screen) scroll = -scroll;
+ tilemap_set_scrollx(bg_tilemap, 0, scroll);
+ tilemap_set_scrollx(fg_tilemap, 0, scroll);
+}
+
+WRITE8_HANDLER( pbaction_flipscreen_w )
+{
+ flip_screen_set(data & 0x01);
+}
+
+static TILE_GET_INFO( get_bg_tile_info )
+{
+ int attr = colorram[tile_index];
+ int code = videoram[tile_index] + 0x10 * (attr & 0x70);
+ int color = attr & 0x0f;
+ int flags = (attr & 0x80) ? TILE_FLIPY : 0;
+
+ SET_TILE_INFO(1, code, color, flags);
+}
+
+static TILE_GET_INFO( get_fg_tile_info )
+{
+ int attr = pbaction_colorram2[tile_index];
+ int code = pbaction_videoram2[tile_index] + 0x10 * (attr & 0x30);
+ int color = attr & 0x0f;
+ int flags = ((attr & 0x40) ? TILE_FLIPX : 0) | ((attr & 0x80) ? TILE_FLIPY : 0);
+
+ SET_TILE_INFO(0, code, color, flags);
+}
+
+VIDEO_START( pbaction )
+{
+ bg_tilemap = tilemap_create(get_bg_tile_info, tilemap_scan_rows,
+ TILEMAP_TYPE_PEN, 8, 8, 32, 32);
+
+ fg_tilemap = tilemap_create(get_fg_tile_info, tilemap_scan_rows,
+ TILEMAP_TYPE_PEN, 8, 8, 32, 32);
+
+ tilemap_set_transparent_pen(fg_tilemap, 0);
+}
+
+static void draw_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect)
+{
+ int offs;
+
+ for (offs = spriteram_size - 4;offs >= 0;offs -= 4)
+ {
+ int sx,sy,flipx,flipy;
+
+ /* if next sprite is double size, skip this one */
+ if (offs > 0 && spriteram[offs - 4] & 0x80) continue;
+
+ sx = spriteram[offs+3];
+ if (spriteram[offs] & 0x80)
+ sy = 225-spriteram[offs+2];
+ else
+ sy = 241-spriteram[offs+2];
+ flipx = spriteram[offs+1] & 0x40;
+ flipy = spriteram[offs+1] & 0x80;
+ if (flip_screen)
+ {
+ if (spriteram[offs] & 0x80)
+ {
+ sx = 224 - sx;
+ sy = 225 - sy;
+ }
+ else
+ {
+ sx = 240 - sx;
+ sy = 241 - sy;
+ }
+ flipx = !flipx;
+ flipy = !flipy;
+ }
+
+ drawgfx(bitmap,machine->gfx[(spriteram[offs] & 0x80) ? 3 : 2], /* normal or double size */
+ spriteram[offs],
+ spriteram[offs + 1] & 0x0f,
+ flipx,flipy,
+ sx + (flip_screen ? scroll : -scroll), sy,
+ cliprect,TRANSPARENCY_PEN,0);
+ }
+}
+
+VIDEO_UPDATE( pbaction )
+{
+ tilemap_draw(bitmap, cliprect, bg_tilemap, 0, 0);
+ draw_sprites(machine, bitmap, cliprect);
+ tilemap_draw(bitmap, cliprect, fg_tilemap, 0, 0);
+ return 0;
+}