#include <vector>
#include <algorithm>
#include "emu.h"
#include "video/segaic24.h"
#include "includes/segas24.h"
namespace {
struct layer_sort {
layer_sort(segas24_mixer *_mixer) { mixer = _mixer; }
bool operator()(int l1, int l2) {
static const int default_pri[12] = { 0, 1, 2, 3, 4, 5, 6, 7, -4, -3, -2, -1 };
int p1 = mixer->get_reg(l1) & 7;
int p2 = mixer->get_reg(l2) & 7;
if(p1 != p2)
return p1 - p2 < 0;
return default_pri[l2] - default_pri[l1] < 0;
}
segas24_mixer *mixer;
};
};
SCREEN_UPDATE(system24)
{
segas24_state *state = screen->machine().driver_data<segas24_state>();
if(state->vmixer->get_reg(13) & 1) {
bitmap_fill(bitmap, 0, get_black_pen(screen->machine()));
return 0;
}
bitmap_fill(screen->machine().priority_bitmap, 0, 0);
bitmap_fill(bitmap, cliprect, 0);
std::vector<int> order;
order.resize(12);
for(int i=0; i<12; i++)
order[i] = i;
std::sort(order.begin(), order.end(), layer_sort(state->vmixer));
int spri[4];
int level = 0;
for(int i=0; i<12; i++)
if(order[i] < 8)
state->vtile->draw(bitmap, cliprect, order[i], level, 0);
else {
spri[order[i]-8] = level;
level++;
}
state->vsprite->draw(bitmap, cliprect, spri);
return 0;
}