aeroboto.c

这个是延伸mame的在wince平台下的游戏模拟器的代码

/***************************************************************************

  vidhrdw.c

  Functions to emulate the video hardware of the machine.

  aeroboto (preliminary)

***************************************************************************/

#include "driver.h"
#include "vidhrdw/generic.h"



unsigned char *aeroboto_videoram;
unsigned char *aeroboto_fgscroll,*aeroboto_bgscroll;
unsigned char *aeroboto_charlookup;

static int charbank;


void aeroboto_gfxctrl_w(int ofset,int data)
{
	/* not sure about this, could be bit 2 */
	charbank = (data & 0x02) >> 1;

	/* there's probably a flip screen here as well */
}



/***************************************************************************

  Draw the game screen in the given osd_bitmap.
  Do NOT call osd_update_display() from this function, it will be called by
  the main emulation engine.

***************************************************************************/
void aeroboto_vh_screenrefresh(struct osd_bitmap *bitmap,int full_refresh)
{
	int offs;


	for (offs = videoram_size - 1;offs >= 0;offs--)
	{
		int sx,sy;


		sx = offs % 32;
		sy = offs / 32;

		drawgfx(bitmap,Machine->gfx[0],
				videoram[offs] + 256 * charbank,
				0,
				0,0,
				8*sx - aeroboto_bgscroll[sy],8*sy,
				&Machine->drv->visible_area,TRANSPARENCY_NONE,0);
		drawgfx(bitmap,Machine->gfx[0],
				videoram[offs] + 256 * charbank,
				0,
				0,0,
				8*sx - aeroboto_bgscroll[sy] + 256,8*sy,
				&Machine->drv->visible_area,TRANSPARENCY_NONE,0);
	}

	for (offs = videoram_size - 1;offs >= 0;offs--)
	{
		int sx,sy;

		sx = offs % 32;
		sy = offs / 32;

		drawgfx(bitmap,Machine->gfx[0],
				aeroboto_videoram[offs] + 256 * charbank,
				0,
				0,0,
				8*sx - aeroboto_fgscroll[sy],8*sy,
				&Machine->drv->visible_area,TRANSPARENCY_PEN,0);
		drawgfx(bitmap,Machine->gfx[0],
				aeroboto_videoram[offs] + 256 * charbank,
				0,
				0,0,
				8*sx - aeroboto_fgscroll[sy] + 256,8*sy,
				&Machine->drv->visible_area,TRANSPARENCY_PEN,0);
	}

	for (offs = spriteram_size-4;offs >= 0;offs -= 4)
	{
		int sx,sy;


		sx = spriteram[offs + 3];
		sy = 239 - spriteram[offs];

		drawgfx(bitmap,Machine->gfx[2],
				spriteram[offs + 1],
				spriteram[offs + 2] & 0x0f,
				0,0,
				sx,sy,
				&Machine->drv->visible_area,TRANSPARENCY_PEN,0);
	}
}