# HG changeset patch
# User John Tsiombikas <nuclear@member.fsf.org>
# Date 1361155286 -7200
# Node ID 57ea4988a9f2322330436b46ef6d8c098b8b9b66
# Parent  e09cbb2e9d4f8c46bb488bca00838d9c54c804c8
added code to dump the ditherblock image

diff -r e09cbb2e9d4f -r 57ea4988a9f2 src/udg.cc
--- a/src/udg.cc	Mon Feb 18 03:46:52 2013 +0200
+++ b/src/udg.cc	Mon Feb 18 04:41:26 2013 +0200
@@ -70,8 +70,13 @@
 
 bool init()
 {
-	float *img = new float[DITHER_SZ * DITHER_SZ * DITHER_LEVELS];
-	float *ptr = img;
+	FILE *fp = fopen("udg.ppm", "wb");
+	if(fp) {
+		fprintf(fp, "P6\n%d %d\n255\n", DITHER_SZ, DITHER_SZ * DITHER_LEVELS);
+	}
+
+	unsigned char *img = new unsigned char[DITHER_SZ * DITHER_SZ * DITHER_LEVELS];
+	unsigned char *ptr = img;
 
 	for(int i=0; i<DITHER_LEVELS; i++) {
 		float val = (float)i / (float)(DITHER_LEVELS - 1);
@@ -79,11 +84,24 @@
 			for(int x=0; x<DITHER_SZ; x++) {
 				/* (1 + M) / (1 + MxN) */
 				float thres = (1.0 + dither_matrix[x][y]) / (1.0 + DITHER_SZ * DITHER_SZ);
-				*ptr++ = val >= thres ? 1.0 : 0.0;
+				*ptr++ = val >= thres ? 255 : 0;
+
+				if(fp) {
+					int r = ptr[-1] ? 246 : 10;
+					int g = ptr[-1] ? 198 : 72;
+					int b = ptr[-1] ? 141 : 85;
+					fputc(r, fp);
+					fputc(g, fp);
+					fputc(b, fp);
+				}
 			}
 		}
 	}
 
+	if(fp) {
+		fclose(fp);
+	}
+
 	if(!(prog = create_program_load("sdr/dither.v.glsl", "sdr/dither.p.glsl"))) {
 		return false;
 	}
@@ -94,7 +112,7 @@
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
-	glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, DITHER_SZ, DITHER_SZ * DITHER_LEVELS, 0, GL_LUMINANCE, GL_FLOAT, img);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, DITHER_SZ, DITHER_SZ * DITHER_LEVELS, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, img);
 
 	if(!init_scroller()) {
 		return false;