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-rw-r--r--src/mame/video/mikie.c171
1 files changed, 171 insertions, 0 deletions
diff --git a/src/mame/video/mikie.c b/src/mame/video/mikie.c
new file mode 100644
index 00000000000..2f924410526
--- /dev/null
+++ b/src/mame/video/mikie.c
@@ -0,0 +1,171 @@
+/***************************************************************************
+
+ video.c
+
+ Functions to emulate the video hardware of the machine.
+
+***************************************************************************/
+
+#include "driver.h"
+
+static int palettebank;
+
+static tilemap *bg_tilemap;
+
+/***************************************************************************
+
+ Convert the color PROMs into a more useable format.
+
+ Mikie has three 256x4 palette PROMs (one per gun) and two 256x4 lookup
+ table PROMs (one for characters, one for sprites).
+ 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 -- RED/GREEN/BLUE
+ -- 470 ohm resistor -- RED/GREEN/BLUE
+ -- 1 kohm resistor -- RED/GREEN/BLUE
+ bit 0 -- 2.2kohm resistor -- RED/GREEN/BLUE
+
+***************************************************************************/
+PALETTE_INIT( mikie )
+{
+ int i;
+ #define TOTAL_COLORS(gfxn) (machine->gfx[gfxn]->total_colors * machine->gfx[gfxn]->color_granularity)
+ #define COLOR(gfxn,offs) (colortable[machine->drv->gfxdecodeinfo[gfxn].color_codes_start + offs])
+
+
+ for (i = 0;i < machine->drv->total_colors;i++)
+ {
+ int bit0,bit1,bit2,bit3,r,g,b;
+
+
+ bit0 = (color_prom[0] >> 0) & 0x01;
+ bit1 = (color_prom[0] >> 1) & 0x01;
+ bit2 = (color_prom[0] >> 2) & 0x01;
+ bit3 = (color_prom[0] >> 3) & 0x01;
+ r = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
+ bit0 = (color_prom[machine->drv->total_colors] >> 0) & 0x01;
+ bit1 = (color_prom[machine->drv->total_colors] >> 1) & 0x01;
+ bit2 = (color_prom[machine->drv->total_colors] >> 2) & 0x01;
+ bit3 = (color_prom[machine->drv->total_colors] >> 3) & 0x01;
+ g = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
+ bit0 = (color_prom[2*machine->drv->total_colors] >> 0) & 0x01;
+ bit1 = (color_prom[2*machine->drv->total_colors] >> 1) & 0x01;
+ bit2 = (color_prom[2*machine->drv->total_colors] >> 2) & 0x01;
+ bit3 = (color_prom[2*machine->drv->total_colors] >> 3) & 0x01;
+ b = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
+
+ palette_set_color(machine,i,MAKE_RGB(r,g,b));
+
+ color_prom++;
+ }
+
+ color_prom += 2*machine->drv->total_colors;
+ /* color_prom now points to the beginning of the character lookup table */
+
+
+ /* there are eight 32 colors palette banks; sprites use colors 0-15 and */
+ /* characters 16-31 of each bank. */
+ for (i = 0;i < TOTAL_COLORS(0)/8;i++)
+ {
+ int j;
+
+
+ for (j = 0;j < 8;j++)
+ COLOR(0,i + j * TOTAL_COLORS(0)/8) = (*color_prom & 0x0f) + 32 * j + 16;
+
+ color_prom++;
+ }
+
+ for (i = 0;i < TOTAL_COLORS(1)/8;i++)
+ {
+ int j;
+
+
+ for (j = 0;j < 8;j++)
+ COLOR(1,i + j * TOTAL_COLORS(1)/8) = (*color_prom & 0x0f) + 32 * j;
+
+ color_prom++;
+ }
+}
+
+WRITE8_HANDLER( mikie_videoram_w )
+{
+ videoram[offset] = data;
+ tilemap_mark_tile_dirty(bg_tilemap, offset);
+}
+
+WRITE8_HANDLER( mikie_colorram_w )
+{
+ colorram[offset] = data;
+ tilemap_mark_tile_dirty(bg_tilemap, offset);
+}
+
+WRITE8_HANDLER( mikie_palettebank_w )
+{
+ if (palettebank != (data & 0x07))
+ {
+ palettebank = data & 0x07;
+ tilemap_mark_all_tiles_dirty(ALL_TILEMAPS);
+ }
+}
+
+WRITE8_HANDLER( mikie_flipscreen_w )
+{
+ if (flip_screen != (data & 0x01))
+ {
+ flip_screen_set(data & 0x01);
+ tilemap_mark_all_tiles_dirty(ALL_TILEMAPS);
+ }
+}
+
+static TILE_GET_INFO( get_bg_tile_info )
+{
+ int code = videoram[tile_index] + ((colorram[tile_index] & 0x20) << 3);
+ int color = (colorram[tile_index] & 0x0f) + 16 * palettebank;
+ int flags = ((colorram[tile_index] & 0x40) ? TILE_FLIPX : 0) | ((colorram[tile_index] & 0x80) ? TILE_FLIPY : 0);
+
+ SET_TILE_INFO(0, code, color, flags);
+}
+
+VIDEO_START( mikie )
+{
+ bg_tilemap = tilemap_create(get_bg_tile_info, tilemap_scan_rows,
+ TILEMAP_TYPE_PEN, 8, 8, 32, 32);
+}
+
+static void draw_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect)
+{
+ int offs;
+
+ for (offs = 0;offs < spriteram_size;offs += 4)
+ {
+ int gfxbank = (spriteram[offs+2] & 0x40) ? 2 : 1;
+ int code = (spriteram[offs + 2] & 0x3f) + ((spriteram[offs + 2] & 0x80) >> 1) + ((spriteram[offs] & 0x40) << 1);
+ int color = (spriteram[offs] & 0x0f) + 16 * palettebank;
+ int sx = spriteram[offs + 3];
+ int sy = 244 - spriteram[offs + 1];
+ int flipx = ~spriteram[offs] & 0x10;
+ int flipy = spriteram[offs] & 0x20;
+
+ if (flip_screen)
+ {
+ sy = 242 - sy;
+ flipy = !flipy;
+ }
+
+ drawgfx(bitmap, machine->gfx[gfxbank],
+ code, color,
+ flipx,flipy,
+ sx,sy,
+ cliprect,
+ TRANSPARENCY_PEN, 0);
+ }
+}
+
+VIDEO_UPDATE( mikie )
+{
+ tilemap_draw(bitmap, cliprect, bg_tilemap, 0, 0);
+ draw_sprites(machine, bitmap, cliprect);
+ return 0;
+}