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Diffstat (limited to 'src/mame/video/1943.c')
-rw-r--r--src/mame/video/1943.c249
1 files changed, 249 insertions, 0 deletions
diff --git a/src/mame/video/1943.c b/src/mame/video/1943.c
new file mode 100644
index 00000000000..7f336789196
--- /dev/null
+++ b/src/mame/video/1943.c
@@ -0,0 +1,249 @@
+#include "driver.h"
+
+#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])
+
+UINT8 *c1943_scrollx;
+UINT8 *c1943_scrolly;
+UINT8 *c1943_bgscrollx;
+
+static int chon, objon, sc1on, sc2on;
+
+static tilemap *bg2_tilemap, *bg_tilemap, *fg_tilemap;
+
+/***************************************************************************
+
+ Convert the color PROMs into a more useable format.
+
+ 1943 has three 256x4 palette PROMs (one per gun) and a lot ;-) of 256x4
+ lookup table PROMs.
+ The palette PROMs are connected to the RGB output this way:
+
+ 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( 1943 )
+{
+ int i;
+
+ for (i = 0; i < machine->drv->total_colors; i++)
+ {
+ int bit0, bit1, bit2, bit3, r, g, b;
+
+ bit0 = (color_prom[i] >> 0) & 0x01;
+ bit1 = (color_prom[i] >> 1) & 0x01;
+ bit2 = (color_prom[i] >> 2) & 0x01;
+ bit3 = (color_prom[i] >> 3) & 0x01;
+
+ r = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
+
+ bit0 = (color_prom[i + machine->drv->total_colors] >> 0) & 0x01;
+ bit1 = (color_prom[i + machine->drv->total_colors] >> 1) & 0x01;
+ bit2 = (color_prom[i + machine->drv->total_colors] >> 2) & 0x01;
+ bit3 = (color_prom[i + machine->drv->total_colors] >> 3) & 0x01;
+
+ g = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;
+
+ bit0 = (color_prom[i + 2*machine->drv->total_colors] >> 0) & 0x01;
+ bit1 = (color_prom[i + 2*machine->drv->total_colors] >> 1) & 0x01;
+ bit2 = (color_prom[i + 2*machine->drv->total_colors] >> 2) & 0x01;
+ bit3 = (color_prom[i + 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 += 3*machine->drv->total_colors;
+ /* color_prom now points to the beginning of the lookup table */
+
+ /* characters use colors 64-79 */
+ for (i = 0;i < TOTAL_COLORS(0);i++)
+ COLOR(0,i) = *(color_prom++) + 64;
+ color_prom += 128; /* skip the bottom half of the PROM - not used */
+
+ /* foreground tiles use colors 0-63 */
+ for (i = 0;i < TOTAL_COLORS(1);i++)
+ {
+ /* color 0 MUST map to pen 0 in order for transparency to work */
+ if (i % machine->gfx[1]->color_granularity == 0)
+ COLOR(1,i) = 0;
+ else
+ COLOR(1,i) = color_prom[0] + 16 * (color_prom[256] & 0x03);
+ color_prom++;
+ }
+ color_prom += TOTAL_COLORS(1);
+
+ /* background tiles use colors 0-63 */
+ for (i = 0;i < TOTAL_COLORS(2);i++)
+ {
+ COLOR(2,i) = color_prom[0] + 16 * (color_prom[256] & 0x03);
+ color_prom++;
+ }
+ color_prom += TOTAL_COLORS(2);
+
+ /* sprites use colors 128-255 */
+ /* bit 3 of BMPROM.07 selects priority over the background, but we handle */
+ /* it differently for speed reasons */
+ for (i = 0;i < TOTAL_COLORS(3);i++)
+ {
+ COLOR(3,i) = color_prom[0] + 16 * (color_prom[256] & 0x07) + 128;
+ color_prom++;
+ }
+ color_prom += TOTAL_COLORS(3);
+}
+
+WRITE8_HANDLER( c1943_videoram_w )
+{
+ videoram[offset] = data;
+ tilemap_mark_tile_dirty(fg_tilemap, offset);
+}
+
+WRITE8_HANDLER( c1943_colorram_w )
+{
+ colorram[offset] = data;
+ tilemap_mark_tile_dirty(fg_tilemap, offset);
+}
+
+WRITE8_HANDLER( c1943_c804_w )
+{
+ int bankaddress;
+ UINT8 *RAM = memory_region(REGION_CPU1);
+
+ /* bits 0 and 1 are coin counters */
+ coin_counter_w(0, data & 0x01);
+ coin_counter_w(1, data & 0x02);
+
+ /* bits 2, 3 and 4 select the ROM bank */
+ bankaddress = 0x10000 + (data & 0x1c) * 0x1000;
+ memory_set_bankptr(1, &RAM[bankaddress]);
+
+ /* bit 5 resets the sound CPU - we ignore it */
+
+ /* bit 6 flips screen */
+ flip_screen_set(data & 0x40);
+
+ /* bit 7 enables characters */
+ chon = data & 0x80;
+}
+
+WRITE8_HANDLER( c1943_d806_w )
+{
+ /* bit 4 enables bg 1 */
+ sc1on = data & 0x10;
+
+ /* bit 5 enables bg 2 */
+ sc2on = data & 0x20;
+
+ /* bit 6 enables sprites */
+ objon = data & 0x40;
+}
+
+static TILE_GET_INFO( c1943_get_bg2_tile_info )
+{
+ UINT8 *tilerom = memory_region(REGION_GFX5) + 0x8000;
+
+ int offs = tile_index * 2;
+ int attr = tilerom[offs + 1];
+ int code = tilerom[offs];
+ int color = (attr & 0x3c) >> 2;
+ int flags = TILE_FLIPYX((attr & 0xc0) >> 6);
+
+ SET_TILE_INFO(2, code, color, flags);
+}
+
+static TILE_GET_INFO( c1943_get_bg_tile_info )
+{
+ UINT8 *tilerom = memory_region(REGION_GFX5);
+
+ int offs = tile_index * 2;
+ int attr = tilerom[offs + 1];
+ int code = tilerom[offs] + ((attr & 0x01) << 8);
+ int color = (attr & 0x3c) >> 2;
+ int flags = TILE_FLIPYX((attr & 0xc0) >> 6);
+
+ SET_TILE_INFO(1, code, color, flags);
+}
+
+static TILE_GET_INFO( c1943_get_fg_tile_info )
+{
+ int attr = colorram[tile_index];
+ int code = videoram[tile_index] + ((attr & 0xe0) << 3);
+ int color = attr & 0x1f;
+
+ SET_TILE_INFO(0, code, color, 0);
+}
+
+VIDEO_START( 1943 )
+{
+ bg2_tilemap = tilemap_create(c1943_get_bg2_tile_info, tilemap_scan_cols,
+ TILEMAP_TYPE_PEN, 32, 32, 2048, 8);
+
+ bg_tilemap = tilemap_create(c1943_get_bg_tile_info, tilemap_scan_cols,
+ TILEMAP_TYPE_PEN, 32, 32, 2048, 8);
+
+ fg_tilemap = tilemap_create(c1943_get_fg_tile_info, tilemap_scan_rows,
+ TILEMAP_TYPE_PEN, 8, 8, 32, 32);
+
+ tilemap_set_transparent_pen(bg_tilemap, 0);
+ tilemap_set_transparent_pen(fg_tilemap, 0);
+}
+
+static void draw_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect, int priority)
+{
+ int offs;
+
+ for (offs = spriteram_size - 32; offs >= 0; offs -= 32)
+ {
+ int attr = spriteram[offs + 1];
+ int code = spriteram[offs] + ((attr & 0xe0) << 3);
+ int color = attr & 0x0f;
+ int sx = spriteram[offs + 3] - ((attr & 0x10) << 4);
+ int sy = spriteram[offs + 2];
+
+ if (flip_screen)
+ {
+ sx = 240 - sx;
+ sy = 240 - sy;
+ }
+
+ // the priority is actually selected by bit 3 of BMPROM.07
+ if (priority)
+ {
+ if (color != 0x0a && color != 0x0b)
+ {
+ drawgfx(bitmap, machine->gfx[3], code, color, flip_screen, flip_screen,
+ sx, sy, cliprect, TRANSPARENCY_PEN, 0);
+ }
+ }
+ else
+ {
+ if (color == 0x0a || color == 0x0b)
+ {
+ drawgfx(bitmap, machine->gfx[3], code, color, flip_screen, flip_screen,
+ sx, sy, cliprect, TRANSPARENCY_PEN, 0);
+ }
+ }
+ }
+}
+
+VIDEO_UPDATE( 1943 )
+{
+ tilemap_set_scrollx(bg2_tilemap, 0, c1943_bgscrollx[0] + 256 * c1943_bgscrollx[1]);
+ tilemap_set_scrollx(bg_tilemap, 0, c1943_scrollx[0] + 256 * c1943_scrollx[1]);
+ tilemap_set_scrolly(bg_tilemap, 0, c1943_scrolly[0]);
+
+ if (sc2on)
+ tilemap_draw(bitmap, cliprect, bg2_tilemap, 0, 0);
+ else
+ fillbitmap(bitmap, get_black_pen(machine), cliprect);
+
+ if (objon) draw_sprites(machine, bitmap, cliprect, 0);
+ if (sc1on) tilemap_draw(bitmap, cliprect, bg_tilemap, 0, 0);
+ if (objon) draw_sprites(machine, bitmap, cliprect, 1);
+ if (chon) tilemap_draw(bitmap, cliprect, fg_tilemap, 0, 0);
+ return 0;
+}