void copy_layer(bitmap_ind16 bitmap, rectangle cliprect, copy_layer_func_t copy_layer_func, int which, int [] sprites_on, rectangle [] sprite_areas)
{
if (which == 0)
{
draw_sprites(bitmap);
}
else
{
copy_layer_func(bitmap, cliprect, which - 1, sprites_on, sprite_areas);
}
}
void copy_layers(bitmap_ind16 bitmap, rectangle cliprect, copy_layer_func_t copy_layer_func, int [] sprites_on, rectangle [] sprite_areas)
{
// fill the screen with the background color
bitmap.fill((uint32_t)(8 * (m_colorbank.op[1] & 0x07)), cliprect);
for (int i = 0; i < 4; i++)
{
int which = m_draw_order[m_video_priority.op0 & 0x1f, i];
copy_layer(bitmap, cliprect, copy_layer_func, which, sprites_on, sprite_areas);
}
}
int video_update_common(bitmap_ind16 bitmap, rectangle cliprect, copy_layer_func_t copy_layer_func)
{
int [] sprites_on = new int[0x20]; // 1 if sprite is active
rectangle [] sprite_areas = new rectangle[0x20]; // areas on bitmap (sprite locations)
set_pens();
draw_layers();
calculate_sprite_areas(sprites_on, sprite_areas);
copy_layers(bitmap, cliprect, copy_layer_func, sprites_on, sprite_areas);
//check_sprite_layer_collision() uses drawn bitmaps, so it must me called _AFTER_ draw_layers()
check_collision(sprites_on, sprite_areas);
return(0);
}