🔧 Tweak incinerate effect

resources/shaders/incinerate.frag

@@ -14,7 +14,7 @@
 // The content from common.glsl is automatically prepended to each shader effect.
 
 uniform vec2 uSeed;
-// uniform vec3 uColor;
+uniform vec3 uColor;
 uniform float uScale;
 // uniform float uWidth;
 uniform float uTurbulence;
@@ -22,9 +22,10 @@ uniform float uTurbulence;
 const float SCORCH_WIDTH = 0.1;
 const float BURN_WIDTH   = 0.02;
 const float SMOKE_WIDTH  = 0.6;
+const float FLAME_WIDTH  = 0.1;
 
 vec4 getFireColor(float val) {
-  return vec4(tritone(val, vec3(0.0), vec3(1.0, 0.8, 0.6), vec3(1.0)), val);
+  return vec4(tritone(val, vec3(0.0), uColor, vec3(1.0)), val);
 }
 
 void main() {
@@ -32,8 +33,9 @@ void main() {
   float hideThreshold = mix(-SCORCH_WIDTH, 1.0 + SMOKE_WIDTH, uProgress);
   vec2 scorchRange    = uForOpening ? vec2(hideThreshold - SCORCH_WIDTH, hideThreshold)
                                     : vec2(hideThreshold, hideThreshold + SCORCH_WIDTH);
-  vec2 smokeRange     = vec2(hideThreshold - SMOKE_WIDTH, hideThreshold);
   vec2 burnRange      = vec2(hideThreshold - BURN_WIDTH, hideThreshold + BURN_WIDTH);
+  vec2 flameRange     = vec2(hideThreshold - FLAME_WIDTH, hideThreshold);
+  vec2 smokeRange     = vec2(hideThreshold - SMOKE_WIDTH, hideThreshold);
 
   vec2 uv = cogl_tex_coord_in[0].st / uScale * uSize;
 
@@ -42,36 +44,51 @@ void main() {
 
   float mask = mix(gradient, noise, 0.15);
 
+  // Now we retrieve the window color. We add some distortion in the scorch zone.
   vec2 distort = vec2(0.0);
 
-  if (!uForOpening && (smokeRange.x < mask && mask < smokeRange.y)) {
-    distort.y += pow(1.0 - (mask - smokeRange.x) / SMOKE_WIDTH, 2.0) * 0.1;
-  }
-
   if ((uForOpening && mask > scorchRange.x) || (!uForOpening && mask <= scorchRange.y)) {
-    distort +=
+    distort =
       0.5 * vec2(dFdx(mask), dFdy(mask)) * (scorchRange.y - mask) / SCORCH_WIDTH * 5.0;
   }
 
   vec4 oColor = getInputColor(cogl_tex_coord_in[0].st + distort);
 
+  // Hide after buring zone has passed.
   if ((uForOpening && mask > smokeRange.y) || (!uForOpening && mask < smokeRange.y)) {
     oColor = vec4(0.0);
   }
 
-  float smoke =
+  float smokeMask =
     smoothstep(0, 1, (mask - smokeRange.x) / SMOKE_WIDTH) * getRelativeEdgeMask(0.1);
-  smoke *=
-    simplex2DFractal(uv * 0.01 + uSeed - smoke * smoke * vec2(0.0, 0.1 * uDuration));
+
+  float smokeNoise = simplex2DFractal(uv * 0.01 + uSeed -
+                                      smokeMask * smokeMask * vec2(0.0, 0.1 * uDuration));
+
+  float flameNoise =
+    simplex2DFractal(uv * 0.02 + uSeed - smokeNoise * vec2(0.0, 1.0 * uDuration) -
+                     vec2(0.0, uProgress * uDuration));
   float emberNoise =
-    simplex2DFractal(uv * 0.075 + uSeed - smoke * vec2(0.0, 0.5 * uDuration));
+    simplex2DFractal(uv * 0.075 + uSeed - smokeMask * vec2(0.0, 0.2 * uDuration));
 
   if (smokeRange.x < mask && mask < smokeRange.y) {
 
-    oColor       = alphaOver(oColor, vec4(0.5 * vec3(smoke), smoke));
-    float embers = clamp(pow(emberNoise + 0.32, 100.0), 0.0, 2.0) * smoke;
-    embers += clamp(pow(emberNoise + 0.32, 10.0), 0.0, 2.0) * smoke;
-    oColor = alphaOver(oColor, getFireColor(embers));
+    float smoke = smokeMask * smokeNoise;
+    oColor      = alphaOver(oColor, vec4(0.5 * vec3(smoke), smoke));
+
+    float embers = clamp(pow(emberNoise + 0.3, 100.0), 0.0, 2.0) * smoke;
+    // embers += clamp(pow(emberNoise + 0.32, 10.0), 0.0, 2.0) * smoke;
+    oColor += getFireColor(embers);
+  }
+
+  if (flameRange.x < mask && mask < flameRange.y) {
+
+    float flameMask =
+      smoothstep(0, 1, (mask - flameRange.x) / FLAME_WIDTH) * getRelativeEdgeMask(0.1);
+
+    float flame = clamp(pow(flameNoise + 0.3, 20.0), 0.0, 2.0) * flameMask;
+    flame += clamp(pow(flameNoise + 0.8, 5.0), 0.0, 2.0) * flameMask * 0.1;
+    oColor += getFireColor(flame);
   }
 
   // Add scorch effect.
@@ -85,10 +102,11 @@ void main() {
     oColor.rgb = mix(oColor.rgb, mix(oColor.rgb, vec3(0.1, 0.05, 0.02), 0.4), scorch);
   }
 
+  // Add burning edge.
   if (burnRange.x < mask && mask < burnRange.y) {
     float fireEdge = smoothstep(1, 0, abs(mask - hideThreshold) / BURN_WIDTH) * oColor.a;
-    fireEdge       = fireEdge * pow(emberNoise + 0.4, 4.0);
-    oColor         = alphaOver(oColor, getFireColor(fireEdge));
+    fireEdge       = fireEdge * pow(flameNoise + 0.4, 4.0);
+    oColor += getFireColor(fireEdge * oColor.a);
   }
 
   setOutputColor(oColor);