/* APPROX. 170 FPS Minimum */
+typedef struct {
+ unsigned int w, h;
+ unsigned char *scans;
+} RLEBitmap;
+
+static RLEBitmap createRLEBitmap(unsigned int w, unsigned int h);
+static destroyRLEBitmap(RLEBitmap b);
+
#define BG_FILENAME "data/grise.png"
#define GROBJ_01_FILENAME "data/grobj_01.png"
static void initScrollTables();
static void updateScrollTables(float dt);
-static void rleEncode(unsigned char *pixels, unsigned int w, unsigned int h);
+static RLEBitmap rleEncode(unsigned char *pixels, unsigned int w, unsigned int h);
static unsigned short *background = 0;
static unsigned int backgroundW = 0;
static int scrollModTable[REFLECTION_HEIGHT];
static float nearScrollAmount = 0.0f;
+static RLEBitmap grobj;
+
static struct screen scr = {
"galaxyrise",
init,
static int init(void)
{
- unsigned char *reflectedObject;
- int reflectedObjectW, reflectedObjectH;
+ unsigned char *tmpBitmap;
+ int tmpBitmapW, tmpBitmapH;
/* Allocate back buffer */
backBuffer = (unsigned short*) malloc(BB_SIZE * BB_SIZE * sizeof(unsigned short));
convert32To16((unsigned int*)background, background, backgroundW * NORMALMAP_SCANLINE); /* Normalmap will keep its 32 bit color */
/* Load reflected objects */
- if (!(reflectedObject = img_load_pixels(GROBJ_01_FILENAME, &reflectedObjectW, &reflectedObjectH, IMG_FMT_GREY8))) {
+ if (!(tmpBitmap = img_load_pixels(GROBJ_01_FILENAME, &tmpBitmapW, &tmpBitmapH, IMG_FMT_GREY8))) {
fprintf(stderr, "failed to load image " GROBJ_01_FILENAME "\n");
return -1;
}
- rleEncode(reflectedObject, reflectedObjectW, reflectedObjectH);
+ grobj = rleEncode(tmpBitmap, tmpBitmapW, tmpBitmapH);
- img_free_pixels(reflectedObject);
+ img_free_pixels(tmpBitmap);
initScrollTables();
backBuffer = 0;
img_free_pixels(background);
+
+ destroyRLEBitmap(grobj);
}
static void start(long trans_time)
dst += BB_SIZE;
}
- /* Create scroll opffsets for all scanlines of the normalmap */
+ /* Create scroll offsets for all scanlines of the normalmap */
updateScrollTables(lastFrameDuration);
- /* Then, render the reflection under the horizon */
- /* dst is already in place */
- src = background + HORIZON_HEIGHT * backgroundW;
+ /* Render the baked reflection one scanline below its place, so that
+ * the displacement that follows will be done in a cache-friendly way
+ */
+ src -= PIXEL_PADDING; /* We want to also fill the PADDING pixels here */
+ dst = backBuffer + (HORIZON_HEIGHT + 1) * BB_SIZE;
+ for (scanline = 0; scanline < REFLECTION_HEIGHT; scanline++) {
+ memcpy(dst, src, (fb_width + PIXEL_PADDING) * 2);
+ src += backgroundW;
+ dst += BB_SIZE;
+ }
+
+ /* Perform displacement */
+ dst = backBuffer + HORIZON_HEIGHT * BB_SIZE + PIXEL_PADDING;
+ src = dst + BB_SIZE; /* The pixels to be displaced are 1 scanline below */
dispScanline = displacementMap;
for (scanline = 0; scanline < REFLECTION_HEIGHT; scanline++) {
for (i = 0; i < fb_width; i++) {
d = dispScanline[(i + scrollTableRounded[scanline]) % scrollModTable[scanline]];
- *dst++ = src[i + scroll + d];
+ *dst++ = src[i + d];
}
src += backgroundW;
dst += BB_SIZE - fb_width;
}
}
-static void rleEncode(unsigned char *pixels, unsigned int w, unsigned int h) {
+/* -------------------------------------------------------------------------------------------------
+ * RLE STUFF
+ * -------------------------------------------------------------------------------------------------
+ */
+/* Limit streak count per scanline so we can directly jump to specific scanline */
+#define RLE_STREAKS_PER_SCANLINE 4
+/* Every streak is encoded by 2 bytes: offset and count of black pixels in the streak */
+#define RLE_BYTES_PER_SCANLINE RLE_STREAKS_PER_SCANLINE * 2
+
+static RLEBitmap createRLEBitmap(unsigned int w, unsigned int h) {
+ RLEBitmap ret;
+ ret.w = w;
+ ret.h = h;
+
+ /* Add some padding at the end of the buffer, with the worst case for a scanline (w/2 streaks) */
+ ret.scans = (unsigned char*) calloc(h * RLE_BYTES_PER_SCANLINE + w, 1);
+
+ return ret;
+}
+
+static destroyRLEBitmap(RLEBitmap b) {
+ free(b.scans);
+}
+
+static RLEBitmap rleEncode(unsigned char *pixels, unsigned int w, unsigned int h) {
int scanline;
int i;
- int skipping = 1;
+ int penActive = 0;
+ int counter = 0;
+ int accum = 0;
+ RLEBitmap ret;
+ unsigned char *output;
+
+ /* https://www.youtube.com/watch?v=RKMR02o1I88&feature=youtu.be&t=55 */
+ ret = createRLEBitmap(w, h);
for (scanline = 0; scanline < h; scanline++) {
+ output = ret.scans + scanline * RLE_BYTES_PER_SCANLINE;
+ accum = 0;
for (i = 0; i < w; i++) {
if (*pixels++) {
-
+ if (penActive) {
+ if (counter >= PIXEL_PADDING) {
+ *output++ = (unsigned char) counter;
+ counter = 0;
+ *output++ = (unsigned char)accum;
+ }
+ counter++;
+ accum++;
+ } else {
+ *output++ = (unsigned char)accum;
+ counter = 1;
+ accum++;
+ penActive = 1;
+ }
+ } else {
+ if (penActive) {
+ *output++ = (unsigned char)counter;
+ counter = 1;
+ accum++;
+ penActive = 0;
+ } else {
+ counter++;
+ accum++;
+ }
}
}
+
+ if (penActive) {
+ *output++ = (unsigned char)counter;
+ }
+ penActive = 0;
+ counter = 0;
}
+
+ return ret;
}