Update blossom template

example/blossom/draw.frag

@@ -12,11 +12,11 @@
     uniform int frame_count;
     #define iResolution resolution
     #define iFrame frame_count
-    #define gl_FragColor fragColor
 
 #else
 
     // Blossom header
+    layout(location = 0) out vec4 fragColor;
     layout(location = 0) uniform vec4 iResolution;
     layout(location = 1) uniform int iFrame;
 
@@ -45,11 +45,13 @@ vec3 noise(vec3 p, float f) {
     return acc.xyz / acc.w;
 }
 
+// rotation matrix
 mat2 rot(float a) {
     float s=sin(a), c=cos(a);
     return mat2(c,-s,s,c);
 }
 
+// Sh4derJockey logo sdf
 float logo(vec2 p) {
     const float t = 0.015;
     const float h = 0.5 * (7.0 / 18.0 + t);
@@ -65,16 +67,22 @@ float logo(vec2 p) {
 float trace(vec3 ro, vec3 rd) {
     float r = 1e32;
 
+    // intersect with one slice at a time
     for(int i = -8; i <= 2; i++) {
+
+        // ray-plane intersection
         float t = (i - ro.y) / rd.y;
         if (t < 0) continue;
 
+        // compute point on plane
         vec3 p = ro + rd * t;
         float s = dot(p, rd);
         p.xz *= rot(0.06 * p.y - 0.5);
 
+        // evaluate logo sdf
         float d = logo(p.xz);
 
+        // add noise pattern
         if (i < 1) {
             d = min(d, abs(noise(p, 5).x) - 0.002);
 
@@ -87,35 +95,47 @@ float trace(vec3 ro, vec3 rd) {
             d = min(d, min(a.x, a.y));
         }
 
+        // update nearest intersection
         if (d < 0.01 * (rv.x - 0.5)) r = min(r, t);
+
+        // cycle random state
         rv = rv.wxyz;
     }
 
     return r;
 }
 
 void main() {
+    // initialise random state
     rv = 7 * cos(iFrame + gl_FragCoord);
     for (int i=0; i<8; i++) shuffle();
 
+    // compute uv coordinates with anti-aliasing
     vec2 aa = rv.xy * 2 - 1;
     vec2 uv = (2 * gl_FragCoord.xy - iResolution.xy + aa) / iResolution.y;
 
+    // compute depth of field parameters
     vec2 a = vec2(1, 2 * pi) * rv.zw;
     vec2 dof = 0.6 * pow(a.x, 0.45) * vec2(cos(a.y),sin(a.y));
 
+    // setup camera
     const float focal = 8.0;
     vec3 ro = vec3(dof, -3.5 * focal);
     vec3 rd = normalize(vec3(uv - focal * dof / length(ro), focal));
 
+    // orbit rotate camera
     ro.yz *= rot(0.7);
     rd.yz *= rot(0.7);
 
+    // update random state
     shuffle();
     shuffle();
     shuffle();
 
+    // trace and compute color
     float t = trace(ro, rd);
     vec3 col = (1 + 2 * vec3(aa, aa.x)) * exp(-0.1*pow(length(ro) - t - 1, 2));
-    gl_FragColor = vec4(col, 1);
+
+    // set output color
+    fragColor = vec4(col, 1);
 }

example/blossom/present.frag

@@ -8,14 +8,14 @@
 
     // compatibility header
     out vec4 fragColor;
-    uniform sampler2D accumulatorTex;
     uniform vec4 resolution;
+    uniform sampler2D accumulatorTex;
     #define iResolution resolution
-    #define gl_FragColor fragColor
 
 #else
 
     // Blossom header
+    layout(location = 0) out vec4 fragColor;
     layout(location = 0) uniform vec4 iResolution;
     layout(binding = 0) uniform sampler2D accumulatorTex;
 
@@ -28,12 +28,14 @@
 void main() {
     ivec2 coord = ivec2(gl_FragCoord.xy);
 
+    // apply unsharp filter
     const float f = 0.2;
     vec4 acc = (1 + 4 * f) * texelFetch(accumulatorTex, coord, 0);
     acc -= f * texelFetch(accumulatorTex, coord + ivec2(0, 1), 0);
     acc -= f * texelFetch(accumulatorTex, coord + ivec2(1, 0), 0);
     acc -= f * texelFetch(accumulatorTex, coord - ivec2(0, 1), 0);
     acc -= f * texelFetch(accumulatorTex, coord - ivec2(1, 0), 0);
 
-    gl_FragColor = vec4(sqrt(acc.rgb / acc.a), 1);
+    // set output color
+    fragColor = vec4(sqrt(acc.rgb / acc.a), 1);
 }