+static GLboolean
+is_sampler_type(GLenum type)
+{
+ switch (type) {
+ case GL_SAMPLER_1D:
+ case GL_SAMPLER_2D:
+ case GL_SAMPLER_3D:
+ case GL_SAMPLER_CUBE:
+ case GL_SAMPLER_1D_SHADOW:
+ case GL_SAMPLER_2D_SHADOW:
+ case GL_SAMPLER_2D_RECT_ARB:
+ case GL_SAMPLER_2D_RECT_SHADOW_ARB:
+ case GL_SAMPLER_1D_ARRAY_EXT:
+ case GL_SAMPLER_2D_ARRAY_EXT:
+ return GL_TRUE;
+ default:
+ return GL_FALSE;
+ }
+}
+
+
+/**
+ * Check if the type given by userType is allowed to set a uniform of the
+ * target type. Generally, equivalence is required, but setting Boolean
+ * uniforms can be done with glUniformiv or glUniformfv.
+ */
+static GLboolean
+compatible_types(GLenum userType, GLenum targetType)
+{
+ if (userType == targetType)
+ return GL_TRUE;
+
+ if (targetType == GL_BOOL && (userType == GL_FLOAT || userType == GL_INT))
+ return GL_TRUE;
+
+ if (targetType == GL_BOOL_VEC2 && (userType == GL_FLOAT_VEC2 ||
+ userType == GL_INT_VEC2))
+ return GL_TRUE;
+
+ if (targetType == GL_BOOL_VEC3 && (userType == GL_FLOAT_VEC3 ||
+ userType == GL_INT_VEC3))
+ return GL_TRUE;
+
+ if (targetType == GL_BOOL_VEC4 && (userType == GL_FLOAT_VEC4 ||
+ userType == GL_INT_VEC4))
+ return GL_TRUE;
+
+ if (is_sampler_type(targetType) && userType == GL_INT)
+ return GL_TRUE;
+
+ return GL_FALSE;
+}
+
+