add - normal optimization to deffered to texture

Author: Hannah Bollar

src/shaders/deferred.frag.glsl.js

@@ -4,6 +4,8 @@ export default function(params) {
   precision highp float;
   
   uniform sampler2D u_gbuffers[${params.numGBuffers}];
+
+  // Redoing the impl from ForwardPlus to get texel index
   
   varying vec2 v_uv;
   

src/shaders/deferredToTexture.frag.glsl

@@ -21,9 +21,14 @@ void main() {
     vec3 norm = applyNormalMap(v_normal, vec3(texture2D(u_normap, v_uv)));
     vec3 col = vec3(texture2D(u_colmap, v_uv));
 
-    // TODO: populate your g buffer
-    // gl_FragData[0] = ??
-    // gl_FragData[1] = ??
-    // gl_FragData[2] = ??
-    // gl_FragData[3] = ??
+    // populate your g buffer
+
+    // optimization to compress the normal vector into x and y components (can just solve for z)
+    // vec4(r, g, b, nor_x), vec4(x, y, z, nor_y)
+    vec3 temp_normal = normalize(vec3(u_viewMatrix * vec4(norm,0.0)));
+    gl_FragData[0] = vec4(col, temp_normal.x);
+    gl_FragData[1] = vec4(v_position, temp_normal.y);
+
+    // if not optimizing the normal then:
+    // gl_FragData[2] = vec4(v_normal, 0.0);
 }