Added [models] example - skybox loading and drawing

examples/models/skybox/skybox.vs

@@ -0,0 +1,24 @@
+#version 330
+
+// input vertex attributes
+in vec3 vertexPosition;
+
+// input uniform values
+uniform mat4 matProjection;
+uniform mat4 matView;
+
+// output vertex attributes (to fragment shader)
+out vec3 fragPosition;
+
+void main()
+{
+    // calculate fragment position based on model transformations
+    fragPosition = vertexPosition;
+
+    // remove translation from the view matrix
+    mat4 rotView = mat4(mat3(matView));
+    vec4 clipPos = matProjection*rotView*vec4(vertexPosition, 1.0);
+
+    // calculate final vertex position
+    gl_Position = clipPos;
+}