added openGL 2 shaders (#version 120)

README.md

@@ -21,6 +21,7 @@ Image warping, as used in this addon, is the process of manipulating an image so
 
 * openFrameworks 0.9 and up
 * OpenGL 3 and up (programmable pipeline)
+* **ADDED** OpenGL 2 compatibility (#version 120 shaders included in openGL2_shaders folder)
 * The included shaders only work with normalized textures (`GL_TEXTURE_2D`) but can be easily modified to work with rectangle textures
 
 #### Controls

openGL2_shaders/ControlPoint.frag

@@ -0,0 +1,19 @@
+#version 120
+
+varying vec3 v;
+varying vec3 N;
+
+varying vec2 vTexCoord;
+varying vec4 vColor;
+
+void main(void) {
+
+	vec2 coord = gl_TexCoord[0].st;
+	vec2 uv = coord * 2.0 - 1.0;
+	float d = dot(uv, uv);
+	float rim = smoothstep(0.7, 0.8, d);
+	rim += smoothstep(0.3, 0.4, d) - smoothstep(0.5, 0.6, d);
+	rim += smoothstep(0.1, 0.0, d);
+	gl_FragColor = mix(vec4( 0.0, 0.0, 0.0, 0.25), vColor, rim);
+
+}

openGL2_shaders/ControlPoint.vert

@@ -0,0 +1,23 @@
+#version 120
+
+varying vec3 v;
+varying vec3 N;
+
+attribute vec4 iPositionScale;
+attribute vec4 iColor;
+
+attribute vec4 position;
+attribute vec2 texcoord;
+attribute vec4 color;
+
+varying vec2 vTexCoord;
+varying vec4 vColor;
+
+void main(void) {
+
+	vTexCoord = texcoord;
+	vColor = gl_Color * iColor;
+  	gl_Position = gl_ModelViewProjectionMatrix * vec4(position.xy * iPositionScale.z + iPositionScale.xy, position.zw);
+
+
+}

openGL2_shaders/WarpBilinear.frag

@@ -0,0 +1,55 @@
+#version 120
+
+varying vec3 v;
+varying vec3 N;
+
+uniform sampler2DRect uTexture;
+uniform vec4 uExtends;
+uniform vec3 uLuminance;
+uniform vec3 uGamma;
+uniform vec4 uEdges;
+uniform vec4 uCorners;
+uniform float uExponent;
+uniform bool uEditing;
+
+float map(float value,float inMin,float inMax,float outMin,float outMax){
+	return outMin + (outMax - outMin) * (value - inMin) / (inMax - inMin);
+}
+
+float grid(vec2 uv,vec2 size){
+	vec2 coord = uv / size;
+	vec2 grid = abs(fract(coord - 0.5) - 0.5) / (2.0 * fwidth(coord));
+	float line = min(grid.x, grid.y);
+	return 1.0 - min(line, 1.0);
+}
+
+void main(void)
+{
+
+	vec2 coord = gl_TexCoord[0].st;
+    vec4 texColor = texture2DRect(uTexture, coord);
+
+	vec2 mapCoord = vec2(map(coord.x, uCorners.x, uCorners.z, 0.0, 1.0), map(coord.y, uCorners.y, uCorners.w, 0.0, 1.0));
+
+	float a = 1.0;
+	if (uEdges.x > 0.0) a *= clamp(mapCoord.x / uEdges.x, 0.0, 1.0);
+	if (uEdges.y > 0.0) a *= clamp(mapCoord.y / uEdges.y, 0.0, 1.0);
+	if (uEdges.z > 0.0) a *= clamp((1.0 - mapCoord.x) / uEdges.z, 0.0, 1.0);
+	if (uEdges.w > 0.0) a *= clamp((1.0 - mapCoord.y) / uEdges.w, 0.0, 1.0);
+
+	const vec3 one = vec3(1.0);
+	vec3 blend = (a < 0.5) ? (uLuminance * pow(2.0 * a, uExponent)) : one - (one - uLuminance) * pow(2.0 * (1.0 - a), uExponent);
+
+	texColor.rgb *= pow(blend, one / uGamma);
+
+	if (uEditing)
+	{
+		float f = grid(mapCoord.xy * uExtends.xy, uExtends.zw);
+		vec4 gridColor = vec4(1.0f);
+		gl_FragColor = mix(texColor, gridColor, f);
+	}
+	else
+	{
+		gl_FragColor = texColor;
+	}
+}

openGL2_shaders/WarpBilinear.vert

@@ -0,0 +1,12 @@
+#version 120
+
+varying vec3 v;
+varying vec3 N;
+
+void main(){
+    v = vec3(gl_ModelViewMatrix * gl_Vertex);
+    N = normalize(gl_NormalMatrix * gl_Normal);
+
+    gl_TexCoord[0] = gl_MultiTexCoord0;
+    gl_Position = ftransform();
+}

openGL2_shaders/WarpPerspective.frag

@@ -0,0 +1,36 @@
+#version 120
+
+varying vec3 v;
+varying vec3 N;
+
+uniform sampler2DRect uTexture;
+uniform vec3 uLuminance;
+uniform vec3 uGamma;
+uniform vec4 uEdges;
+uniform vec4 uCorners;
+uniform float uExponent;
+
+float map(float value, float inMin, float inMax, float outMin, float outMax){
+  return outMin + (outMax - outMin) * (value - inMin) / (inMax - inMin);
+}
+
+void main(void){
+
+	vec2 coord = gl_TexCoord[0].st;
+    vec4 texColor = texture2DRect(uTexture, coord);
+
+	vec2 mapCoord = vec2(map(coord.x, uCorners.x, uCorners.z, 0.0, 1.0), map(coord.y, uCorners.y, uCorners.w, 0.0, 1.0));
+
+	float a = 1.0;
+	if (uEdges.x > 0.0) a *= clamp(mapCoord.x / uEdges.x, 0.0, 1.0);
+	if (uEdges.y > 0.0) a *= clamp(mapCoord.y / uEdges.y, 0.0, 1.0);
+	if (uEdges.z > 0.0) a *= clamp((1.0 - mapCoord.x) / uEdges.z, 0.0, 1.0);
+	if (uEdges.w > 0.0) a *= clamp((1.0 - mapCoord.y) / uEdges.w, 0.0, 1.0);
+
+	const vec3 one = vec3(1.0);
+	vec3 blend = (a < 0.5) ? (uLuminance * pow(2.0 * a, uExponent)) : one - (one - uLuminance) * pow(2.0 * (1.0 - a), uExponent);
+
+	texColor.rgb *= pow(blend, one / uGamma);
+
+	gl_FragColor = texColor;
+}

openGL2_shaders/WarpPerspective.vert

@@ -0,0 +1,12 @@
+#version 120
+
+varying vec3 v;
+varying vec3 N;
+
+void main(){
+    v = vec3(gl_ModelViewMatrix * gl_Vertex);
+    N = normalize(gl_NormalMatrix * gl_Normal);
+
+    gl_TexCoord[0] = gl_MultiTexCoord0;
+    gl_Position = ftransform();
+}