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Diffstat (limited to 'src/mame/video/terracre.c')
-rw-r--r--src/mame/video/terracre.c224
1 files changed, 224 insertions, 0 deletions
diff --git a/src/mame/video/terracre.c b/src/mame/video/terracre.c
new file mode 100644
index 00000000000..582c22f5b15
--- /dev/null
+++ b/src/mame/video/terracre.c
@@ -0,0 +1,224 @@
+/***************************************************************************
+
+ video.c
+
+ Functions to emulate the video hardware of the machine.
+
+***************************************************************************/
+
+#include "driver.h"
+
+static UINT16 xscroll;
+static UINT16 yscroll;
+static tilemap *background, *foreground;
+static const UINT8 *spritepalettebank;
+
+UINT16 *amazon_videoram;
+
+static
+TILE_GET_INFO( get_bg_tile_info )
+{
+ /* xxxx.----.----.----
+ * ----.xx--.----.----
+ * ----.--xx.xxxx.xxxx */
+ unsigned data = amazon_videoram[tile_index];
+ unsigned color = data>>11;
+ SET_TILE_INFO( 1,data&0x3ff,color,0 );
+}
+
+static
+TILE_GET_INFO( get_fg_tile_info )
+{
+ int data = videoram16[tile_index];
+ SET_TILE_INFO( 0,data&0xff,0,0 );
+}
+
+static void draw_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect )
+{
+ const gfx_element *pGfx = machine->gfx[2];
+ const UINT16 *pSource = spriteram16;
+ int i;
+ int transparent_pen;
+
+ if( pGfx->total_elements > 0x200 )
+ { /* HORE HORE Kid */
+ transparent_pen = 0xf;
+ }
+ else
+ {
+ transparent_pen = 0x0;
+ }
+ for( i=0; i<0x200; i+=8 )
+ {
+ int tile = pSource[1]&0xff;
+ int attrs = pSource[2];
+ int flipx = attrs&0x04;
+ int flipy = attrs&0x08;
+ int color = (attrs&0xf0)>>4;
+ int sx = (pSource[3] & 0xff) - 0x80 + 256 * (attrs & 1);
+ int sy = 240 - (pSource[0] & 0xff);
+
+ if( transparent_pen )
+ {
+ int bank;
+
+ if( attrs&0x02 ) tile |= 0x200;
+ if( attrs&0x10 ) tile |= 0x100;
+
+ bank = (tile&0xfc)>>1;
+ if( tile&0x200 ) bank |= 0x80;
+ if( tile&0x100 ) bank |= 0x01;
+
+ color &= 0xe;
+ color += 16*(spritepalettebank[bank]&0xf);
+ }
+ else
+ {
+ if( attrs&0x02 ) tile|= 0x100;
+ color += 16 * (spritepalettebank[(tile>>1)&0xff] & 0x0f);
+ }
+
+ if (flip_screen)
+ {
+ sx=240-sx;
+ sy=240-sy;
+ flipx = !flipx;
+ flipy = !flipy;
+ }
+
+ drawgfx(
+ bitmap,pGfx,tile, color,flipx,flipy,sx,sy,cliprect,TRANSPARENCY_PEN,transparent_pen );
+
+ pSource += 4;
+ }
+}
+
+PALETTE_INIT( amazon )
+{
+ #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])
+ int i;
+ 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 lookup table */
+
+
+ /* characters use colors 0-15 */
+ for (i = 0;i < TOTAL_COLORS(0);i++)
+ COLOR(0,i) = i;
+
+ /* background tiles use colors 192-255 in four banks */
+ /* the bottom two bits of the color code select the palette bank for */
+ /* pens 0-7; the top two bits for pens 8-15. */
+ for (i = 0;i < TOTAL_COLORS(1);i++)
+ {
+ if (i & 8) COLOR(1,i) = 192 + (i & 0x0f) + ((i & 0xc0) >> 2);
+ else COLOR(1,i) = 192 + (i & 0x0f) + ((i & 0x30) >> 0);
+ }
+
+ /* sprites use colors 128-191 in four banks */
+ /* The lookup table tells which colors to pick from the selected bank */
+ /* the bank is selected by another PROM and depends on the top 8 bits of */
+ /* the sprite code. The PROM selects the bank *separately* for pens 0-7 and */
+ /* 8-15 (like for tiles). */
+ for (i = 0;i < TOTAL_COLORS(2)/16;i++)
+ {
+ int j;
+
+ for (j = 0;j < 16;j++)
+ {
+ if (i & 8)
+ COLOR(2,i + j * (TOTAL_COLORS(2)/16)) = 128 + ((j & 0x0c) << 2) + (*color_prom & 0x0f);
+ else
+ COLOR(2,i + j * (TOTAL_COLORS(2)/16)) = 128 + ((j & 0x03) << 4) + (*color_prom & 0x0f);
+ }
+
+ color_prom++;
+ }
+
+ /* color_prom now points to the beginning of the sprite palette bank table */
+ spritepalettebank = color_prom; /* we'll need it at run time */
+}
+
+WRITE16_HANDLER( amazon_background_w )
+{
+ COMBINE_DATA( &amazon_videoram[offset] );
+ tilemap_mark_tile_dirty( background, offset );
+}
+
+WRITE16_HANDLER( amazon_foreground_w )
+{
+ COMBINE_DATA( &videoram16[offset] );
+ tilemap_mark_tile_dirty( foreground, offset );
+}
+
+WRITE16_HANDLER( amazon_flipscreen_w )
+{
+ if( ACCESSING_LSB )
+ {
+ coin_counter_w( 0, data&0x01 );
+ coin_counter_w( 1, (data&0x02)>>1 );
+ flip_screen_set(data&0x04);
+ }
+}
+
+WRITE16_HANDLER( amazon_scrolly_w )
+{
+ COMBINE_DATA(&yscroll);
+ tilemap_set_scrolly(background,0,yscroll);
+}
+
+WRITE16_HANDLER( amazon_scrollx_w )
+{
+ COMBINE_DATA(&xscroll);
+ tilemap_set_scrollx(background,0,xscroll);
+}
+
+VIDEO_START( amazon )
+{
+ background = tilemap_create(get_bg_tile_info,tilemap_scan_cols,TILEMAP_TYPE_PEN,16,16,64,32);
+ foreground = tilemap_create(get_fg_tile_info,tilemap_scan_cols,TILEMAP_TYPE_PEN,8,8,64,32);
+ tilemap_set_transparent_pen(foreground,0xf);
+
+ /* register for saving */
+ state_save_register_global(xscroll);
+ state_save_register_global(yscroll);
+}
+
+VIDEO_UPDATE( amazon )
+{
+ if( xscroll&0x2000 )
+ {
+ fillbitmap( bitmap,get_black_pen(machine),cliprect );
+ }
+ else
+ {
+ tilemap_draw( bitmap,cliprect, background, 0, 0 );
+ }
+ draw_sprites( machine, bitmap,cliprect );
+ tilemap_draw( bitmap,cliprect, foreground, 0, 0 );
+ return 0;
+}