commit 4d38d86b2c5e572b1ea5ff4a5a84acb7ab5b87fc
author Zack Rusin <zack@tungstengraphics.com> Mon Jun 16 13:19:41 2008 -0400
committer Zack Rusin <zack@tungstengraphics.com> Mon Jul 21 19:19:22 2008 -0400
tree 22c5ad1630b6cab24cfb852f5f319a0825a661bd
parent ec9c79a7dd468f3bd0483d3a9d59809bf019e54b

add edge detection to that example

progs/glsl/convolutions.c

diff --git a/progs/glsl/convolutions.c b/progs/glsl/convolutions.c
index be88771..9b9ee53 100644
--- a/progs/glsl/convolutions.c
+++ b/progs/glsl/convolutions.c
@@ -12,6 +12,7 @@
    SHARPEN,
    MEAN_REMOVAL,
    EMBOSS,
+   EDGE_DETECT,
    NO_FILTER,
    LAST
 };
@@ -146,6 +147,17 @@
       color[2] = 0.5;
       color[3] = 0.5;
       break;
+   case EDGE_DETECT:
+      k[0] =  1; k[1] =  1; k[2] =  1;
+      k[3] =  0; k[4] =  0; k[5] =  0;
+      k[6] = -1; k[7] = -1; k[8] = -1;
+
+      *scale = 1.;
+      color[0] = 0.5;
+      color[1] = 0.5;
+      color[2] = 0.5;
+      color[3] = 0.5;
+      break;
    case NO_FILTER:
       k[0] =  0; k[1] =  0; k[2] =  0;
       k[3] =  0; k[4] =  1; k[5] =  0;
@@ -294,6 +306,7 @@
    glutAddMenuEntry("Sharpen", SHARPEN);
    glutAddMenuEntry("Mean removal", MEAN_REMOVAL);
    glutAddMenuEntry("Emboss", EMBOSS);
+   glutAddMenuEntry("Edge detect", EDGE_DETECT);
    glutAddMenuEntry("None", NO_FILTER);
 
    glutAddMenuEntry("Quit", QUIT);