add RiskyJumps' scanlines-sine-abs shader

misc/scanlines-sine-abs.slang

@@ -0,0 +1,73 @@
+#version 450
+
+/*
+    Scanlines Sine Absolute Value
+    An ultra light scanline shader
+    by RiskyJumps
+	license: public domain
+*/
+
+layout(push_constant) uniform Push
+{
+	vec4 SourceSize;
+	vec4 OriginalSize;
+	vec4 OutputSize;
+	uint FrameCount;
+	float amp;
+	float phase;
+	float lines_black;
+	float lines_white;
+} params;
+
+#pragma parameter amp          "Amplitude"      1.2500  0.000 2.000 0.05
+#pragma parameter phase        "Phase"          0.5000  0.000 2.000 0.05
+#pragma parameter lines_black  "Lines Blacks"   0.0000  0.000 1.000 0.05
+#pragma parameter lines_white  "Lines Whites"   1.0000  0.000 2.000 0.05
+
+layout(std140, set = 0, binding = 0) uniform UBO
+{
+	mat4 MVP;
+} global;
+
+#define freq             0.500000
+#define offset           0.000000
+#define pi               3.141592654
+
+#pragma stage vertex
+layout(location = 0) in vec4 Position;
+layout(location = 1) in vec2 TexCoord;
+layout(location = 0) out vec2 vTexCoord;
+layout(location = 1) out float angle;
+
+void main()
+{
+   gl_Position = global.MVP * Position;
+   vTexCoord = TexCoord;
+   
+   float omega = 2.0 * pi * freq;              // Angular frequency
+   angle = vTexCoord.y * omega * params.SourceSize.y + params.phase;
+}
+
+#pragma stage fragment
+layout(location = 0) in vec2 vTexCoord;
+layout(location = 1) in float angle;
+layout(location = 0) out vec4 FragColor;
+layout(set = 0, binding = 2) uniform sampler2D Source;
+
+void main()
+{
+    vec3 color = texture(Source, vTexCoord).xyz;
+    float grid;
+ 
+    float lines;
+ 
+    lines = sin(angle);
+    lines *= params.amp;
+    lines += offset;
+    lines = abs(lines);
+    lines *= params.lines_white - params.lines_black;
+    lines += params.lines_black;
+    color *= lines;
+ 
+    FragColor = vec4(color.xyz, 1.0);
+}