Black and White postprocessing

Author: Pilzschaf

shaders/color_frag.spv

@@ -5,4 +5,6 @@ glslc.exe -fshader-stage=frag color_frag.glsl -o color_frag.spv
 glslc.exe -fshader-stage=vert texture_vert.glsl -o texture_vert.spv
 glslc.exe -fshader-stage=frag texture_frag.glsl -o texture_frag.spv
 glslc.exe -fshader-stage=vert model_vert.glsl -o model_vert.spv
-glslc.exe -fshader-stage=frag model_frag.glsl -o model_frag.spv
+glslc.exe -fshader-stage=frag model_frag.glsl -o model_frag.spv
+glslc.exe -fshader-stage=vert postprocess_vert.glsl -o postprocess_vert.spv
+glslc.exe -fshader-stage=frag postprocess_frag.glsl -o postprocess_frag.spv

shaders/color_vert.spv

@@ -6,4 +6,6 @@ glslc -fshader-stage=frag color_frag.glsl -o color_frag.spv
 glslc -fshader-stage=vert texture_vert.glsl -o texture_vert.spv
 glslc -fshader-stage=frag texture_frag.glsl -o texture_frag.spv
 glslc -fshader-stage=vert model_vert.glsl -o model_vert.spv
-glslc -fshader-stage=frag model_frag.glsl -o model_frag.spv
+glslc -fshader-stage=frag model_frag.glsl -o model_frag.spv
+glslc -fshader-stage=vert postprocess_vert.glsl -o postprocess_vert.spv
+glslc -fshader-stage=frag postprocess_frag.glsl -o postprocess_frag.spv

shaders/compile.bat

@@ -0,0 +1,10 @@
+#version 450 core
+
+layout(set = 0, input_attachment_index = 0, binding = 0) uniform subpassInput in_color;
+
+layout(location = 0) out vec4 out_color;
+
+void main() {
+    vec4 color = subpassLoad(in_color);
+    out_color = vec4(vec3(length(color.rgb)/sqrt(3.0)), color.a);
+}

shaders/compile.sh

@@ -0,0 +1,34 @@
+#version 450 core
+
+//Basic Buffer/Layout-less fullscreen triangle vertex shader
+vec2 triangleVertex(in int vertID, out vec2 texcoord) {
+    /*
+    //See: https://web.archive.org/web/20140719063725/http://www.altdev.co/2011/08/08/interesting-vertex-shader-trick/
+       1
+    ( 0, 2)
+    [-1, 3]   [ 3, 3]
+        .
+        |`.
+        |  `.
+        |    `.
+        '------`
+       0         2
+    ( 0, 0)   ( 2, 0)
+    [-1,-1]   [ 3,-1]
+    ID=0 -> Pos=[-1,-1], Tex=(0,0)
+    ID=1 -> Pos=[-1, 3], Tex=(0,2)
+    ID=2 -> Pos=[ 3,-1], Tex=(2,0)
+    */
+
+    texcoord.x = (vertID == 2) ?  2.0 :  0.0;
+    texcoord.y = (vertID == 1) ?  2.0 :  0.0;
+
+	return texcoord * vec2(2.0, -2.0) + vec2(-1.0, 1.0);
+}
+
+void main() {
+    vec2 texcoord;
+    vec2 pos = triangleVertex(gl_VertexIndex, texcoord);
+
+    gl_Position = vec4(pos, 1.0, 1.0);
+}