+/**
+ * Do we need to clamp the results of the given texture env/combine mode?
+ * If the inputs to the mode are in [0,1] we don't always have to clamp
+ * the results.
+ */
+static GLboolean
+need_saturate( GLuint mode )
+{
+ switch (mode) {
+ case MODE_REPLACE:
+ case MODE_MODULATE:
+ case MODE_INTERPOLATE:
+ return GL_FALSE;
+ case MODE_ADD:
+ case MODE_ADD_SIGNED:
+ case MODE_SUBTRACT:
+ case MODE_DOT3_RGB:
+ case MODE_DOT3_RGB_EXT:
+ case MODE_DOT3_RGBA:
+ case MODE_DOT3_RGBA_EXT:
+ case MODE_MODULATE_ADD_ATI:
+ case MODE_MODULATE_SIGNED_ADD_ATI:
+ case MODE_MODULATE_SUBTRACT_ATI:
+ case MODE_ADD_PRODUCTS:
+ case MODE_ADD_PRODUCTS_SIGNED:
+ case MODE_BUMP_ENVMAP_ATI:
+ return GL_TRUE;
+ default:
+ assert(0);
+ return GL_FALSE;
+ }
+}
+
+
+