progs/vpglsl: Fix psiz-mul.glsl compilation error on Mac OS.

(cherry picked from commit b98db7bf697c3ed6e6df303e9dd66f7ac31eb3e2)

diff --git a/progs/vpglsl/psiz-mul.glsl b/progs/vpglsl/psiz-mul.glsl
index 77f4a46..d2a90d8 100644 (file)
--- a/progs/vpglsl/psiz-mul.glsl
+++ b/progs/vpglsl/psiz-mul.glsl
@@ -1,6 +1,6 @@
 
 void main() {
     gl_FrontColor = gl_Color;
-    gl_PointSize = 10 * gl_Color.x;
+    gl_PointSize = 10.0 * gl_Color.x;
     gl_Position = gl_Vertex;
 }