Add GLUT_ALPHA for softpipe

46 files changed, 46 insertions, 46 deletions

diff --git a/progs/trivial/clear.c b/progs/trivial/clear.c
index 7e7ca58..69931b5 100644
--- a/progs/trivial/clear.c
+++ b/progs/trivial/clear.c
@@ -108,7 +108,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/dlist-dangling.c b/progs/trivial/dlist-dangling.c
index 97f878e..00a7507 100644
--- a/progs/trivial/dlist-dangling.c
+++ b/progs/trivial/dlist-dangling.c
@@ -131,7 +131,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/dlist-edgeflag-dangling.c b/progs/trivial/dlist-edgeflag-dangling.c
index 31300ef..b993946 100644
--- a/progs/trivial/dlist-edgeflag-dangling.c
+++ b/progs/trivial/dlist-edgeflag-dangling.c
@@ -134,7 +134,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/dlist-edgeflag.c b/progs/trivial/dlist-edgeflag.c
index fa97f04..9e190db 100644
--- a/progs/trivial/dlist-edgeflag.c
+++ b/progs/trivial/dlist-edgeflag.c
@@ -138,7 +138,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/line-clip.c b/progs/trivial/line-clip.c
index 9acd12a..fd79d04 100644
--- a/progs/trivial/line-clip.c
+++ b/progs/trivial/line-clip.c
@@ -122,7 +122,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/line-cull.c b/progs/trivial/line-cull.c
index 8999a8f..038004b 100644
--- a/progs/trivial/line-cull.c
+++ b/progs/trivial/line-cull.c
@@ -118,7 +118,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/line-userclip-clip.c b/progs/trivial/line-userclip-clip.c
index b24d845..5c9c1b3 100644
--- a/progs/trivial/line-userclip-clip.c
+++ b/progs/trivial/line-userclip-clip.c
@@ -124,7 +124,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/line-userclip-nop-clip.c b/progs/trivial/line-userclip-nop-clip.c
index e2e0b85..a6ee44f 100644
--- a/progs/trivial/line-userclip-nop-clip.c
+++ b/progs/trivial/line-userclip-nop-clip.c
@@ -124,7 +124,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/line-userclip-nop.c b/progs/trivial/line-userclip-nop.c
index eacee06..cebea5f 100644
--- a/progs/trivial/line-userclip-nop.c
+++ b/progs/trivial/line-userclip-nop.c
@@ -124,7 +124,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/line-userclip.c b/progs/trivial/line-userclip.c
index 6af9143..ecfd28c 100644
--- a/progs/trivial/line-userclip.c
+++ b/progs/trivial/line-userclip.c
@@ -124,7 +124,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/line.c b/progs/trivial/line.c
index 58bad91..ff18f07 100644
--- a/progs/trivial/line.c
+++ b/progs/trivial/line.c
@@ -122,7 +122,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/lineloop-clip.c b/progs/trivial/lineloop-clip.c
index d8645ee..2110567 100644
--- a/progs/trivial/lineloop-clip.c
+++ b/progs/trivial/lineloop-clip.c
@@ -118,7 +118,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/lineloop.c b/progs/trivial/lineloop.c
index 7500c54..fab7d1e 100644
--- a/progs/trivial/lineloop.c
+++ b/progs/trivial/lineloop.c
@@ -118,7 +118,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/point-clip.c b/progs/trivial/point-clip.c
index 3279204..7fec54e 100644
--- a/progs/trivial/point-clip.c
+++ b/progs/trivial/point-clip.c
@@ -120,7 +120,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/point-param.c b/progs/trivial/point-param.c
index c542468..c50b7cb 100644
--- a/progs/trivial/point-param.c
+++ b/progs/trivial/point-param.c
@@ -127,7 +127,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/point-wide.c b/progs/trivial/point-wide.c
index 473ca04..196e09c 100644
--- a/progs/trivial/point-wide.c
+++ b/progs/trivial/point-wide.c
@@ -122,7 +122,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/point.c b/progs/trivial/point.c
index 87465bf..8dabfb6 100644
--- a/progs/trivial/point.c
+++ b/progs/trivial/point.c
@@ -120,7 +120,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/poly-flat.c b/progs/trivial/poly-flat.c
index 747b24d..a847d68 100644
--- a/progs/trivial/poly-flat.c
+++ b/progs/trivial/poly-flat.c
@@ -122,7 +122,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/poly-unfilled.c b/progs/trivial/poly-unfilled.c
index e0ae463..ae092a8 100644
--- a/progs/trivial/poly-unfilled.c
+++ b/progs/trivial/poly-unfilled.c
@@ -121,7 +121,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/poly.c b/progs/trivial/poly.c
index bdb9e27..2f254de 100644
--- a/progs/trivial/poly.c
+++ b/progs/trivial/poly.c
@@ -120,7 +120,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/quad-clip-all-vertices.c b/progs/trivial/quad-clip-all-vertices.c
index 019ef0c..3e0f3d9 100644
--- a/progs/trivial/quad-clip-all-vertices.c
+++ b/progs/trivial/quad-clip-all-vertices.c
@@ -120,7 +120,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/quad-clip-nearplane.c b/progs/trivial/quad-clip-nearplane.c
index 7e12e58..e76eb29 100644
--- a/progs/trivial/quad-clip-nearplane.c
+++ b/progs/trivial/quad-clip-nearplane.c
@@ -120,7 +120,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/quad-clip.c b/progs/trivial/quad-clip.c
index 9f3a45c..504fef3 100644
--- a/progs/trivial/quad-clip.c
+++ b/progs/trivial/quad-clip.c
@@ -120,7 +120,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/quad-degenerate.c b/progs/trivial/quad-degenerate.c
index b14b0f1..8304740 100644
--- a/progs/trivial/quad-degenerate.c
+++ b/progs/trivial/quad-degenerate.c
@@ -125,7 +125,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/quad-flat.c b/progs/trivial/quad-flat.c
index d6e9f02..bd8be7c 100644
--- a/progs/trivial/quad-flat.c
+++ b/progs/trivial/quad-flat.c
@@ -130,7 +130,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/quad-offset-factor.c b/progs/trivial/quad-offset-factor.c
index 861d346..becc885 100644
--- a/progs/trivial/quad-offset-factor.c
+++ b/progs/trivial/quad-offset-factor.c
@@ -149,7 +149,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB | GLUT_DEPTH;
+    type = GLUT_RGB | GLUT_ALPHA | GLUT_DEPTH;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/quad-offset-unfilled.c b/progs/trivial/quad-offset-unfilled.c
index 1cecf3c..32b2129 100644
--- a/progs/trivial/quad-offset-unfilled.c
+++ b/progs/trivial/quad-offset-unfilled.c
@@ -149,7 +149,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB | GLUT_DEPTH;
+    type = GLUT_RGB | GLUT_ALPHA | GLUT_DEPTH;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/quad-offset-units.c b/progs/trivial/quad-offset-units.c
index 5c41be3..afffebb 100644
--- a/progs/trivial/quad-offset-units.c
+++ b/progs/trivial/quad-offset-units.c
@@ -148,7 +148,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB | GLUT_DEPTH;
+    type = GLUT_RGB | GLUT_ALPHA | GLUT_DEPTH;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/quad-tex-3d.c b/progs/trivial/quad-tex-3d.c
index 0b2dcc0..fd02d9d 100644
--- a/progs/trivial/quad-tex-3d.c
+++ b/progs/trivial/quad-tex-3d.c
@@ -159,7 +159,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/quad-unfilled.c b/progs/trivial/quad-unfilled.c
index 9d63d2d..9d0087c 100644
--- a/progs/trivial/quad-unfilled.c
+++ b/progs/trivial/quad-unfilled.c
@@ -121,7 +121,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/quads.c b/progs/trivial/quads.c
index 1ca82cd..307a9e0 100644
--- a/progs/trivial/quads.c
+++ b/progs/trivial/quads.c
@@ -138,7 +138,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/quadstrip-flat.c b/progs/trivial/quadstrip-flat.c
index 061a0e4..d02135f 100644
--- a/progs/trivial/quadstrip-flat.c
+++ b/progs/trivial/quadstrip-flat.c
@@ -132,7 +132,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/quadstrip.c b/progs/trivial/quadstrip.c
index 342463f..ff8644b 100644
--- a/progs/trivial/quadstrip.c
+++ b/progs/trivial/quadstrip.c
@@ -126,7 +126,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/tri-blend.c b/progs/trivial/tri-blend.c
index 284d15f..58c451c 100644
--- a/progs/trivial/tri-blend.c
+++ b/progs/trivial/tri-blend.c
@@ -132,7 +132,7 @@ void keyboard(unsigned char key, int x, int y)
 int main(int argc, char** argv)
 {
    glutInit(&argc, argv);
-   glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
+   glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_ALPHA);
    glutInitWindowSize (200, 200);
    glutCreateWindow (argv[0]);
    init();
diff --git a/progs/trivial/tri-cull.c b/progs/trivial/tri-cull.c
index 20aeaf1..fa51f51 100644
--- a/progs/trivial/tri-cull.c
+++ b/progs/trivial/tri-cull.c
@@ -118,7 +118,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/tri-dlist.c b/progs/trivial/tri-dlist.c
index e0ab285..c21c471 100644
--- a/progs/trivial/tri-dlist.c
+++ b/progs/trivial/tri-dlist.c
@@ -132,7 +132,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/tri-edgeflag.c b/progs/trivial/tri-edgeflag.c
index bdc0eaa..838f2b0 100644
--- a/progs/trivial/tri-edgeflag.c
+++ b/progs/trivial/tri-edgeflag.c
@@ -123,7 +123,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/tri-flat-clip.c b/progs/trivial/tri-flat-clip.c
index fafa649..155b0c4 100644
--- a/progs/trivial/tri-flat-clip.c
+++ b/progs/trivial/tri-flat-clip.c
@@ -119,7 +119,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/tri-flat.c b/progs/trivial/tri-flat.c
index fb2cdbd..0583a2a 100644
--- a/progs/trivial/tri-flat.c
+++ b/progs/trivial/tri-flat.c
@@ -119,7 +119,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/tri-tex-3d.c b/progs/trivial/tri-tex-3d.c
index 6a9d1d1..613803f 100644
--- a/progs/trivial/tri-tex-3d.c
+++ b/progs/trivial/tri-tex-3d.c
@@ -152,7 +152,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/tri-unfilled-clip.c b/progs/trivial/tri-unfilled-clip.c
index d486af2..df161df 100644
--- a/progs/trivial/tri-unfilled-clip.c
+++ b/progs/trivial/tri-unfilled-clip.c
@@ -119,7 +119,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/tri-unfilled-smooth.c b/progs/trivial/tri-unfilled-smooth.c
index e41903a..f70c1cd 100644
--- a/progs/trivial/tri-unfilled-smooth.c
+++ b/progs/trivial/tri-unfilled-smooth.c
@@ -132,7 +132,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/tri-unfilled-userclip.c b/progs/trivial/tri-unfilled-userclip.c
index dc93a8f..9201f9d 100644
--- a/progs/trivial/tri-unfilled-userclip.c
+++ b/progs/trivial/tri-unfilled-userclip.c
@@ -123,7 +123,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/tri-unfilled.c b/progs/trivial/tri-unfilled.c
index 73961bc..1e44823 100644
--- a/progs/trivial/tri-unfilled.c
+++ b/progs/trivial/tri-unfilled.c
@@ -120,7 +120,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/tri-userclip.c b/progs/trivial/tri-userclip.c
index cde9662..ccf631d 100644
--- a/progs/trivial/tri-userclip.c
+++ b/progs/trivial/tri-userclip.c
@@ -122,7 +122,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);
 
diff --git a/progs/trivial/tristrip.c b/progs/trivial/tristrip.c
index fa82a73..51ea4f2 100644
--- a/progs/trivial/tristrip.c
+++ b/progs/trivial/tristrip.c
@@ -120,7 +120,7 @@ int main(int argc, char **argv)
 
     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 
-    type = GLUT_RGB;
+    type = GLUT_RGB | GLUT_ALPHA;
     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
     glutInitDisplayMode(type);