Disabled external gits

cs440-acg/ext/nanogui/resources/imageview_vertex.gles

@@ -0,0 +1,14 @@
+precision highp float;
+
+uniform mat4 matrix_image;
+uniform mat4 matrix_background;
+attribute vec2 position;
+varying vec2 position_background;
+varying vec2 uv;
+
+void main() {
+    vec4 p = vec4(position, 0.0, 1.0);
+    gl_Position = matrix_image * p;
+    position_background = (matrix_background * p).xy;
+    uv = position;
+}