X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=src%2Fgrise.c;h=45fb1376e07340d3f06e0c55d02b2efd838dcd71;hb=14e38e29d030add566b19a06468902c447f1e1b1;hp=7e57508561f3045fd9052c677a1ce19aec73d26a;hpb=67ecd561eda2d5ca1a9a67588f01bd9d530751c0;p=dosdemo

diff --git a/src/grise.c b/src/grise.c
index 7e57508..45fb137 100644
--- a/src/grise.c
+++ b/src/grise.c
@@ -9,7 +9,16 @@
 
 /* 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"
 
 #define BB_SIZE 512	/* Let's use a power of 2. Maybe we'll zoom/rotate the effect */
 
@@ -38,6 +47,8 @@ static void processNormal();
 static void initScrollTables();
 static void updateScrollTables(float dt);
 
+static RLEBitmap rleEncode(unsigned char *pixels, unsigned int w, unsigned int h);
+
 static unsigned short *background = 0;
 static unsigned int backgroundW = 0;
 static unsigned int backgroundH = 0;
@@ -55,8 +66,10 @@ static int scrollTableRounded[REFLECTION_HEIGHT];
 static int scrollModTable[REFLECTION_HEIGHT];
 static float nearScrollAmount = 0.0f;
 
+static RLEBitmap grobj;
+
 static struct screen scr = {
-	"Galaxy rise",
+	"galaxyrise",
 	init,
 	destroy,
 	start,
@@ -72,9 +85,13 @@ struct screen *grise_screen(void)
 
 static int init(void)
 {
+	unsigned char *tmpBitmap;
+	int tmpBitmapW, tmpBitmapH;
+
 	/* Allocate back buffer */
 	backBuffer = (unsigned short*) malloc(BB_SIZE * BB_SIZE * sizeof(unsigned short));
 
+	/* grise.png contains the background (horizon), baked reflection and normalmap for displacement */
 	if (!(background = img_load_pixels(BG_FILENAME, &backgroundW, &backgroundH, IMG_FMT_RGBA32))) {
 		fprintf(stderr, "failed to load image " BG_FILENAME "\n");
 		return -1;
@@ -83,6 +100,16 @@ static int init(void)
 	/* Convert to 16bpp */
 	convert32To16((unsigned int*)background, background, backgroundW * NORMALMAP_SCANLINE); /* Normalmap will keep its 32 bit color */
 
+	/* Load reflected objects */
+	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;
+	}
+
+	grobj = rleEncode(tmpBitmap, tmpBitmapW, tmpBitmapH);
+
+	img_free_pixels(tmpBitmap);
+
 	initScrollTables();
 
 	processNormal();
@@ -100,6 +127,8 @@ static void destroy(void)
 	backBuffer = 0;
 
 	img_free_pixels(background);
+
+	destroyRLEBitmap(grobj);
 }
 
 static void start(long trans_time)
@@ -131,17 +160,28 @@ static void draw(void)
 		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;
@@ -246,3 +286,81 @@ static void updateScrollTables(float dt) {
 		scrollTableRounded[i] = (int)(scrollTable[i] + 0.5f) % scrollModTable[i];
 	}
 }
+
+/* -------------------------------------------------------------------------------------------------
+ *                                   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 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;
+}