Uploaded shaders for GLSL 120

16 files changed, 608 insertions, 0 deletions

diff --git a/examples/shaders/resources/shaders/glsl120/base.fs b/examples/shaders/resources/shaders/glsl120/base.fs
new file mode 100644
index 00000000..9c685eb9
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/base.fs
@@ -0,0 +1,24 @@
+#version 120
+
+precision mediump float;
+
+// Input vertex attributes (from vertex shader)
+varying vec2 fragTexCoord;
+varying vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// NOTE: Add here your custom variables
+uniform vec2 resolution = vec2(800, 450);
+
+void main()
+{
+    // Texel color fetching from texture sampler
+    vec4 texelColor = texture2D(texture0, fragTexCoord);
+    
+    // NOTE: Implement here your fragment shader code
+    
+    gl_FragColor = texelColor*colDiffuse;
+}
\ No newline at end of file
diff --git a/examples/shaders/resources/shaders/glsl120/base.vs b/examples/shaders/resources/shaders/glsl120/base.vs
new file mode 100644
index 00000000..674153d8
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/base.vs
@@ -0,0 +1,26 @@
+#version 120
+
+// Input vertex attributes
+attribute vec3 vertexPosition;
+attribute vec2 vertexTexCoord;
+attribute vec3 vertexNormal;
+attribute vec4 vertexColor;
+
+// Input uniform values
+uniform mat4 mvp;
+
+// Output vertex attributes (to fragment shader)
+varying vec2 fragTexCoord;
+varying vec4 fragColor;
+
+// NOTE: Add here your custom variables 
+
+void main()
+{
+    // Send vertex attributes to fragment shader
+    fragTexCoord = vertexTexCoord;
+    fragColor = vertexColor;
+    
+    // Calculate final vertex position
+    gl_Position = mvp*vec4(vertexPosition, 1.0);
+}
\ No newline at end of file
diff --git a/examples/shaders/resources/shaders/glsl120/bloom.fs b/examples/shaders/resources/shaders/glsl120/bloom.fs
new file mode 100644
index 00000000..cd9f8cbe
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/bloom.fs
@@ -0,0 +1,39 @@
+#version 120
+
+precision mediump float;
+
+// Input vertex attributes (from vertex shader)
+varying vec2 fragTexCoord;
+varying vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// NOTE: Add here your custom variables
+
+const vec2 size = vec2(800, 450);   // render size
+const float samples = 5.0;          // pixels per axis; higher = bigger glow, worse performance
+const float quality = 2.5; 	        // lower = smaller glow, better quality
+
+void main()
+{
+    vec4 sum = vec4(0);
+    vec2 sizeFactor = vec2(1)/size*quality;
+
+    // Texel color fetching from texture sampler
+    vec4 source = texture2D(texture0, fragTexCoord);
+
+    const int range = 2;            // should be = (samples - 1)/2;
+
+    for (int x = -range; x <= range; x++)
+    {
+        for (int y = -range; y <= range; y++)
+        {
+            sum += texture2D(texture0, fragTexCoord + vec2(x, y)*sizeFactor);
+        }
+    }
+
+    // Calculate final fragment color
+    gl_FragColor = ((sum/(samples*samples)) + source)*colDiffuse;
+}
\ No newline at end of file
diff --git a/examples/shaders/resources/shaders/glsl120/blur.fs b/examples/shaders/resources/shaders/glsl120/blur.fs
new file mode 100644
index 00000000..e2b04ad1
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/blur.fs
@@ -0,0 +1,34 @@
+#version 120
+
+precision mediump float;
+
+// Input vertex attributes (from vertex shader)
+varying vec2 fragTexCoord;
+varying vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// NOTE: Add here your custom variables
+
+// NOTE: Render size values must be passed from code
+const float renderWidth = 800.0;
+const float renderHeight = 450.0;
+
+vec3 offset = vec3(0.0, 1.3846153846, 3.2307692308);
+vec3 weight = vec3(0.2270270270, 0.3162162162, 0.0702702703);
+
+void main() 
+{ 
+    // Texel color fetching from texture sampler
+    vec3 tc = texture2D(texture0, fragTexCoord).rgb*weight.x;
+    
+    tc += texture2D(texture0, fragTexCoord + vec2(offset.y)/renderWidth, 0.0).rgb*weight.y;
+    tc += texture2D(texture0, fragTexCoord - vec2(offset.y)/renderWidth, 0.0).rgb*weight.y;
+    
+    tc += texture2D(texture0, fragTexCoord + vec2(offset.z)/renderWidth, 0.0).rgb*weight.z;
+    tc += texture2D(texture0, fragTexCoord - vec2(offset.z)/renderWidth, 0.0).rgb*weight.z;
+
+    gl_FragColor = vec4(tc, 1.0);
+}
\ No newline at end of file
diff --git a/examples/shaders/resources/shaders/glsl120/cross_hatching.fs b/examples/shaders/resources/shaders/glsl120/cross_hatching.fs
new file mode 100644
index 00000000..17d9c6a3
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/cross_hatching.fs
@@ -0,0 +1,47 @@
+# version 120
+
+precision mediump float;
+
+// Input vertex attributes (from vertex shader)
+varying vec2 fragTexCoord;
+varying vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// NOTE: Add here your custom variables
+
+float hatchOffsetY = 5.0;
+float lumThreshold01 = 0.9;
+float lumThreshold02 = 0.7;
+float lumThreshold03 = 0.5;
+float lumThreshold04 = 0.3;
+
+void main() 
+{
+    vec3 tc = vec3(1.0, 1.0, 1.0);
+    float lum = length(texture2D(texture0, fragTexCoord).rgb);
+
+    if (lum < lumThreshold01) 
+    {
+        if (mod(gl_FragCoord.x + gl_FragCoord.y, 10.0) == 0.0) tc = vec3(0.0, 0.0, 0.0);
+    }  
+
+    if (lum < lumThreshold02) 
+    {
+        if (mod(gl_FragCoord .x - gl_FragCoord .y, 10.0) == 0.0) tc = vec3(0.0, 0.0, 0.0);
+    }  
+
+    if (lum < lumThreshold03) 
+    {
+        if (mod(gl_FragCoord .x + gl_FragCoord .y - hatchOffsetY, 10.0) == 0.0) tc = vec3(0.0, 0.0, 0.0);
+    }  
+
+    if (lum < lumThreshold04) 
+    {
+        if (mod(gl_FragCoord .x - gl_FragCoord .y - hatchOffsetY, 10.0) == 0.0) tc = vec3(0.0, 0.0, 0.0);
+    }
+
+    gl_FragColor = vec4(tc, 1.0);
+}
\ No newline at end of file
diff --git a/examples/shaders/resources/shaders/glsl120/cross_stitching.fs b/examples/shaders/resources/shaders/glsl120/cross_stitching.fs
new file mode 100644
index 00000000..fe60675a
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/cross_stitching.fs
@@ -0,0 +1,57 @@
+# version 120
+
+precision mediump float;
+
+// Input vertex attributes (from vertex shader)
+varying vec2 fragTexCoord;
+varying vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// NOTE: Add here your custom variables
+
+// NOTE: Render size values must be passed from code
+const float renderWidth = 800.0;
+const float renderHeight = 450.0;
+
+float stitchingSize = 6.0;
+int invert = 0;
+
+vec4 PostFX(sampler2D tex, vec2 uv)
+{
+    vec4 c = vec4(0.0);
+    float size = stitchingSize;
+    vec2 cPos = uv * vec2(renderWidth, renderHeight);
+    vec2 tlPos = floor(cPos / vec2(size, size));
+    tlPos *= size;
+
+    int remX = int(mod(cPos.x, size));
+    int remY = int(mod(cPos.y, size));
+    
+    if (remX == 0 && remY == 0) tlPos = cPos;
+    
+    vec2 blPos = tlPos;
+    blPos.y += (size - 1.0);
+    
+    if ((remX == remY) || (((int(cPos.x) - int(blPos.x)) == (int(blPos.y) - int(cPos.y)))))
+    {
+        if (invert == 1) c = vec4(0.2, 0.15, 0.05, 1.0);
+        else c = texture2D(tex, tlPos * vec2(1.0/renderWidth, 1.0/renderHeight)) * 1.4;
+    }
+    else
+    {
+        if (invert == 1) c = texture2D(tex, tlPos * vec2(1.0/renderWidth, 1.0/renderHeight)) * 1.4;
+        else c = vec4(0.0, 0.0, 0.0, 1.0);
+    }
+    
+    return c;
+}
+
+void main()
+{
+    vec3 tc = PostFX(texture0, fragTexCoord).rgb;
+
+    gl_FragColor = vec4(tc, 1.0);
+}
\ No newline at end of file
diff --git a/examples/shaders/resources/shaders/glsl120/distortion.fs b/examples/shaders/resources/shaders/glsl120/distortion.fs
new file mode 100644
index 00000000..568c50bf
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/distortion.fs
@@ -0,0 +1,54 @@
+#version 120
+
+precision mediump float;
+
+// Input vertex attributes (from vertex shader)
+varying vec2 fragTexCoord;
+
+// Input uniform values
+uniform sampler2D texture0;
+
+// NOTE: Default parameters for Oculus Rift DK2 device
+const vec2 LeftLensCenter = vec2(0.2863248, 0.5);
+const vec2 RightLensCenter = vec2(0.7136753, 0.5);
+const vec2 LeftScreenCenter = vec2(0.25, 0.5);
+const vec2 RightScreenCenter = vec2(0.75, 0.5);
+const vec2 Scale = vec2(0.25, 0.45);
+const vec2 ScaleIn = vec2(4.0, 2.5);
+const vec4 HmdWarpParam = vec4(1.0, 0.22, 0.24, 0.0);
+const vec4 ChromaAbParam = vec4(0.996, -0.004, 1.014, 0.0);
+
+void main()
+{
+    // The following two variables need to be set per eye
+    vec2 LensCenter = fragTexCoord.x < 0.5 ? LeftLensCenter : RightLensCenter;
+    vec2 ScreenCenter = fragTexCoord.x < 0.5 ? LeftScreenCenter : RightScreenCenter;
+    
+    // Scales input texture coordinates for distortion: vec2 HmdWarp(vec2 fragTexCoord, vec2 LensCenter)
+    vec2 theta = (fragTexCoord - LensCenter)*ScaleIn;   // Scales to [-1, 1]
+    float rSq = theta.x*theta.x + theta.y*theta.y;
+    vec2 theta1 = theta*(HmdWarpParam.x + HmdWarpParam.y*rSq + HmdWarpParam.z*rSq*rSq + HmdWarpParam.w*rSq*rSq*rSq);
+    //vec2 tc = LensCenter + Scale*theta1;
+    
+    // Detect whether blue texture coordinates are out of range since these will scaled out the furthest
+    vec2 thetaBlue = theta1*(ChromaAbParam.z + ChromaAbParam.w*rSq);
+    vec2 tcBlue = LensCenter + Scale*thetaBlue;
+
+    if (any(bvec2(clamp(tcBlue, ScreenCenter - vec2(0.25, 0.5), ScreenCenter + vec2(0.25, 0.5)) - tcBlue))) gl_FragColor = vec4(0.0, 0.0, 0.0, 1.0);
+    else
+    {
+        // Do blue texture lookup
+        float blue = texture2D(texture0, tcBlue).b;
+
+        // Do green lookup (no scaling)
+        vec2 tcGreen = LensCenter + Scale*theta1;
+        float green = texture2D(texture0, tcGreen).g;
+
+        // Do red scale and lookup
+        vec2 thetaRed = theta1*(ChromaAbParam.x + ChromaAbParam.y*rSq);
+        vec2 tcRed = LensCenter + Scale*thetaRed;
+        float red = texture2D(texture0, tcRed).r;
+
+        gl_FragColor = vec4(red, green, blue, 1.0);
+    }
+}
diff --git a/examples/shaders/resources/shaders/glsl120/dream_vision.fs b/examples/shaders/resources/shaders/glsl120/dream_vision.fs
new file mode 100644
index 00000000..93cec8fb
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/dream_vision.fs
@@ -0,0 +1,37 @@
+#version 120
+
+precision mediump float;
+
+// Input vertex attributes (from vertex shader)
+varying vec2 fragTexCoord;
+varying vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// NOTE: Add here your custom variables
+
+void main()
+{
+    vec4 color = texture2D(texture0, fragTexCoord);
+
+    color += texture2D(texture0, fragTexCoord + 0.001);
+    color += texture2D(texture0, fragTexCoord + 0.003);
+    color += texture2D(texture0, fragTexCoord + 0.005);
+    color += texture2D(texture0, fragTexCoord + 0.007);
+    color += texture2D(texture0, fragTexCoord + 0.009);
+    color += texture2D(texture0, fragTexCoord + 0.011);
+
+    color += texture2D(texture0, fragTexCoord - 0.001);
+    color += texture2D(texture0, fragTexCoord - 0.003);
+    color += texture2D(texture0, fragTexCoord - 0.005);
+    color += texture2D(texture0, fragTexCoord - 0.007);
+    color += texture2D(texture0, fragTexCoord - 0.009);
+    color += texture2D(texture0, fragTexCoord - 0.011);
+
+    color.rgb = vec3((color.r + color.g + color.b)/3.0);
+    color = color/9.5;
+
+    gl_FragColor = color;
+}			
\ No newline at end of file
diff --git a/examples/shaders/resources/shaders/glsl120/fisheye.fs b/examples/shaders/resources/shaders/glsl120/fisheye.fs
new file mode 100644
index 00000000..afac3d4a
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/fisheye.fs
@@ -0,0 +1,43 @@
+#version 120
+
+precision mediump float;
+
+// Input vertex attributes (from vertex shader)
+varying vec2 fragTexCoord;
+varying vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// NOTE: Add here your custom variables
+
+const float PI = 3.1415926535;
+
+void main()
+{
+    float aperture = 178.0;
+    float apertureHalf = 0.5 * aperture * (PI / 180.0);
+    float maxFactor = sin(apertureHalf);
+
+    vec2 uv = vec2(0.0);
+    vec2 xy = 2.0 * fragTexCoord.xy - 1.0;
+    float d = length(xy);
+    
+    if (d < (2.0 - maxFactor))
+    {
+        d = length(xy * maxFactor);
+        float z = sqrt(1.0 - d * d);
+        float r = atan(d, z) / PI;
+        float phi = atan(xy.y, xy.x);
+
+        uv.x = r * cos(phi) + 0.5;
+        uv.y = r * sin(phi) + 0.5;
+    }
+    else
+    {
+        uv = fragTexCoord.xy;
+    }
+
+    gl_FragColor = texture2D(texture0, uv);
+}
\ No newline at end of file
diff --git a/examples/shaders/resources/shaders/glsl120/grayscale.fs b/examples/shaders/resources/shaders/glsl120/grayscale.fs
new file mode 100644
index 00000000..470a4222
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/grayscale.fs
@@ -0,0 +1,25 @@
+#version 120
+
+precision mediump float;
+
+// Input vertex attributes (from vertex shader)
+varying vec2 fragTexCoord;
+varying vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// NOTE: Add here your custom variables
+
+void main()
+{
+    // Texel color fetching from texture sampler
+    vec4 texelColor = texture2D(texture0, fragTexCoord)*colDiffuse*fragColor;
+    
+    // Convert texel color to grayscale using NTSC conversion weights
+    float gray = dot(texelColor.rgb, vec3(0.299, 0.587, 0.114));
+    
+    // Calculate final fragment color
+    gl_FragColor = vec4(gray, gray, gray, texelColor.a);
+}
\ No newline at end of file
diff --git a/examples/shaders/resources/shaders/glsl120/pixelizer.fs b/examples/shaders/resources/shaders/glsl120/pixelizer.fs
new file mode 100644
index 00000000..cea6b5e0
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/pixelizer.fs
@@ -0,0 +1,32 @@
+#version 120
+
+precision mediump float;
+
+// Input vertex attributes (from vertex shader)
+varying vec2 fragTexCoord;
+varying vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// NOTE: Add here your custom variables 
+
+// NOTE: Render size values must be passed from code
+const float renderWidth = 800.0;
+const float renderHeight = 450.0;
+
+float pixelWidth = 5.0;
+float pixelHeight = 5.0;
+
+void main() 
+{ 
+    float dx = pixelWidth*(1.0/renderWidth);
+    float dy = pixelHeight*(1.0/renderHeight);
+    
+    vec2 coord = vec2(dx*floor(fragTexCoord.x/dx), dy*floor(fragTexCoord.y/dy));
+    
+    vec3 tc = texture2D(texture0, coord).rgb;
+
+    gl_FragColor = vec4(tc, 1.0);
+}
\ No newline at end of file
diff --git a/examples/shaders/resources/shaders/glsl120/posterization.fs b/examples/shaders/resources/shaders/glsl120/posterization.fs
new file mode 100644
index 00000000..a9a5f246
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/posterization.fs
@@ -0,0 +1,29 @@
+#version 120
+
+precision mediump float;
+
+// Input vertex attributes (from vertex shader)
+varying vec2 fragTexCoord;
+varying vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// NOTE: Add here your custom variables
+
+float gamma = 0.6;
+float numColors = 8.0;
+
+void main() 
+{ 
+    vec3 color = texture2D(texture0, fragTexCoord.xy).rgb;
+    
+    color = pow(color, vec3(gamma, gamma, gamma));
+    color = color*numColors;
+    color = floor(color);
+    color = color/numColors;
+    color = pow(color, vec3(1.0/gamma));
+    
+    gl_FragColor = vec4(color, 1.0);
+}
\ No newline at end of file
diff --git a/examples/shaders/resources/shaders/glsl120/predator.fs b/examples/shaders/resources/shaders/glsl120/predator.fs
new file mode 100644
index 00000000..c471f89d
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/predator.fs
@@ -0,0 +1,31 @@
+#version 120
+
+precision mediump float;
+
+// Input vertex attributes (from vertex shader)
+varying vec2 fragTexCoord;
+varying vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// NOTE: Add here your custom variables
+
+void main() 
+{
+    vec3 color = texture2D(texture0, fragTexCoord).rgb;
+    vec3 colors[3];
+    colors[0] = vec3(0.0, 0.0, 1.0);
+    colors[1] = vec3(1.0, 1.0, 0.0);
+    colors[2] = vec3(1.0, 0.0, 0.0);
+    
+    float lum = (color.r + color.g + color.b)/3.0;
+
+    vec3 tc = vec3(0.0, 0.0, 0.0);
+    
+    if (lum < 0.5) tc = mix(colors[0], colors[1], lum/0.5);
+    else tc = mix(colors[1], colors[2], (lum - 0.5)/0.5);
+
+    gl_FragColor = vec4(tc, 1.0);
+}
\ No newline at end of file
diff --git a/examples/shaders/resources/shaders/glsl120/scanlines.fs b/examples/shaders/resources/shaders/glsl120/scanlines.fs
new file mode 100644
index 00000000..f279f347
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/scanlines.fs
@@ -0,0 +1,44 @@
+#version 120
+
+precision mediump float;
+
+// Input vertex attributes (from vertex shader)
+varying vec2 fragTexCoord;
+varying vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// NOTE: Add here your custom variables
+
+float offset = 0.0;
+float frequency = 450.0/3.0;
+
+uniform float time;
+
+void main()
+{
+/*
+    // Scanlines method 1
+    float tval = 0; //time
+    vec2 uv = 0.5 + (fragTexCoord - 0.5)*(0.9 + 0.01*sin(0.5*tval));
+
+    vec4 color = texture2D(texture0, fragTexCoord);
+
+    color = clamp(color*0.5 + 0.5*color*color*1.2, 0.0, 1.0);
+    color *= 0.5 + 0.5*16.0*uv.x*uv.y*(1.0 - uv.x)*(1.0 - uv.y);
+    color *= vec4(0.8, 1.0, 0.7, 1);
+    color *= 0.9 + 0.1*sin(10.0*tval + uv.y*1000.0);
+    color *= 0.97 + 0.03*sin(110.0*tval);
+
+    fragColor = color;
+*/
+    // Scanlines method 2
+    float globalPos = (fragTexCoord.y + offset) * frequency;
+    float wavePos = cos((fract(globalPos) - 0.5)*3.14);
+    
+    vec4 color = texture2D(texture0, fragTexCoord);
+
+    gl_FragColor = mix(vec4(0.0, 0.3, 0.0, 0.0), color, wavePos);
+}
\ No newline at end of file
diff --git a/examples/shaders/resources/shaders/glsl120/sobel.fs b/examples/shaders/resources/shaders/glsl120/sobel.fs
new file mode 100644
index 00000000..128ca423
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/sobel.fs
@@ -0,0 +1,40 @@
+#version 120
+
+precision mediump float;
+
+// Input vertex attributes (from vertex shader)
+varying vec2 fragTexCoord;
+varying vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// NOTE: Add here your custom variables
+vec2 resolution = vec2(800.0, 450.0);
+
+void main() 
+{
+	float x = 1.0/resolution.x;
+	float y = 1.0/resolution.y;
+    
+	vec4 horizEdge = vec4(0.0);
+	horizEdge -= texture2D(texture0, vec2(fragTexCoord.x - x, fragTexCoord.y - y))*1.0;
+	horizEdge -= texture2D(texture0, vec2(fragTexCoord.x - x, fragTexCoord.y    ))*2.0;
+	horizEdge -= texture2D(texture0, vec2(fragTexCoord.x - x, fragTexCoord.y + y))*1.0;
+	horizEdge += texture2D(texture0, vec2(fragTexCoord.x + x, fragTexCoord.y - y))*1.0;
+	horizEdge += texture2D(texture0, vec2(fragTexCoord.x + x, fragTexCoord.y    ))*2.0;
+	horizEdge += texture2D(texture0, vec2(fragTexCoord.x + x, fragTexCoord.y + y))*1.0;
+    
+	vec4 vertEdge = vec4(0.0);
+	vertEdge -= texture2D(texture0, vec2(fragTexCoord.x - x, fragTexCoord.y - y))*1.0;
+	vertEdge -= texture2D(texture0, vec2(fragTexCoord.x    , fragTexCoord.y - y))*2.0;
+	vertEdge -= texture2D(texture0, vec2(fragTexCoord.x + x, fragTexCoord.y - y))*1.0;
+	vertEdge += texture2D(texture0, vec2(fragTexCoord.x - x, fragTexCoord.y + y))*1.0;
+	vertEdge += texture2D(texture0, vec2(fragTexCoord.x    , fragTexCoord.y + y))*2.0;
+	vertEdge += texture2D(texture0, vec2(fragTexCoord.x + x, fragTexCoord.y + y))*1.0;
+    
+	vec3 edge = sqrt((horizEdge.rgb*horizEdge.rgb) + (vertEdge.rgb*vertEdge.rgb));
+	
+	gl_FragColor = vec4(edge, texture2D(texture0, fragTexCoord).a);
+}
\ No newline at end of file
diff --git a/examples/shaders/resources/shaders/glsl120/swirl.fs b/examples/shaders/resources/shaders/glsl120/swirl.fs
new file mode 100644
index 00000000..7cb24e2a
--- /dev/null
+++ b/examples/shaders/resources/shaders/glsl120/swirl.fs
@@ -0,0 +1,46 @@
+#version 120
+
+precision mediump float;
+
+// Input vertex attributes (from vertex shader)
+varying vec2 fragTexCoord;
+varying vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// NOTE: Add here your custom variables
+
+// NOTE: Render size values should be passed from code
+const float renderWidth = 800;
+const float renderHeight = 450;
+
+float radius = 250.0;
+float angle = 0.8;
+
+uniform vec2 center;
+
+void main()
+{
+    vec2 texSize = vec2(renderWidth, renderHeight);
+    vec2 tc = fragTexCoord*texSize;
+    tc -= center;
+    
+    float dist = length(tc);
+
+    if (dist < radius) 
+    {
+        float percent = (radius - dist)/radius;
+        float theta = percent*percent*angle*8.0;
+        float s = sin(theta);
+        float c = cos(theta);
+        
+        tc = vec2(dot(tc, vec2(c, -s)), dot(tc, vec2(s, c)));
+    }
+
+    tc += center;
+    vec4 color = texture2D(texture0, tc/texSize)*colDiffuse*fragColor;;
+
+    gl_FragColor = vec4(color.rgb, 1.0);;
+}
\ No newline at end of file