[orx-jumpflood] Make module multiplatform

orx-jumpflood/src/shaders/glsl/pixel-direction.frag

@@ -0,0 +1,59 @@
+
+/*
+use #define OUTPUT_DISTANCE to output distance
+use #define OUTPUT_DIRECTION to output direction
+*/
+
+uniform sampler2D tex0;
+uniform sampler2D tex1;
+uniform vec2 originalSize;
+uniform vec2 directionalField;
+uniform float distanceScale;
+uniform bool normalizedDistance;
+uniform bool unitDirection;
+uniform bool flipV;
+uniform bool outputIds;
+in vec2 v_texCoord0;
+
+out vec4 o_color;
+
+void main() {
+    vec2 sizeDF = vec2(textureSize(tex0, 0)); // this is always square
+    vec2 sizeTF = vec2(textureSize(tex1, 0)); // this can be non-square
+
+    vec2 pixelPosition = v_texCoord0;
+    vec4 textureData = texture(tex0, v_texCoord0);
+    vec2 centroidPixelPosition =  textureData.xy;
+
+
+    vec2 pixelDistance = (centroidPixelPosition - pixelPosition) * sizeDF;
+
+    if (flipV) {
+        pixelDistance *= vec2(1.0, -1.0);
+    }
+
+    if (unitDirection) {
+        float length = length(pixelDistance);
+        if (length >= 1E-6) {
+            pixelDistance /= length;
+        }
+    }
+
+    vec2 dfTf = sizeDF / sizeTF; // texture adjusment factor
+
+    float outputData = (!outputIds) ? texture(tex1, v_texCoord0 * dfTf).r : textureData.b;
+
+    #ifdef OUTPUT_DIRECTION
+    if (!normalizedDistance) {
+        o_color = vec4(pixelDistance * distanceScale, outputData, 1.0);
+    } else if (!unitDirection) {
+        o_color = vec4(pixelDistance / originalSize, outputData, 1.0);
+    }
+    #else
+    if (!normalizedDistance) {
+        o_color = vec4( length(pixelDistance * distanceScale).xx, outputData, 1.0);
+    } else if (!unitDirection) {
+        o_color = vec4( length(pixelDistance / originalSize).xx, outputData, 1.0);
+    }
+    #endif
+}