+// double, for overdraw guard
+#define VRAM_SIZE (1024 * 512 * 2 * 2)
+
+static int map_vram(void)
+{
+ gpu.vram = gpu.mmap(VRAM_SIZE);
+ if (gpu.vram != NULL) {
+ gpu.vram += 4096 / 2;
+ return 0;
+ }
+ else {
+ fprintf(stderr, "could not map vram, expect crashes\n");
+ return -1;
+ }
+}
+