Added ContourPoints and Threshold filters

orx-jumpflood/src/main/kotlin/JumpFlood.kt

@@ -12,10 +12,14 @@ class JumpFlood : Filter(filterShaderFromUrl(resourceUrl("/shaders/gl3/jumpflood
 }
 
 class PixelDistance : Filter(filterShaderFromUrl(resourceUrl("/shaders/gl3/pixel-distance.frag")))
+class ContourPoints : Filter(filterShaderFromUrl(resourceUrl("/shaders/gl3/contour-points.frag")))
+class Threshold : Filter(filterShaderFromUrl(resourceUrl("/shaders/gl3/threshold.frag")))
 
 val encodePoints by lazy { EncodePoints() }
 val jumpFlood by lazy { JumpFlood() }
 val pixelDistance by lazy { PixelDistance() }
+val contourPoints by lazy { ContourPoints() }
+val threshold by lazy { Threshold() }
 
 /** [points] is square and power of 2 */
 fun jumpFlood(points: ColorBuffer, coordinates: List<ColorBuffer>) {

orx-jumpflood/src/main/resources/shaders/gl3/contour-points.frag

@@ -0,0 +1,24 @@
+#version 330 core
+
+uniform sampler2D tex0;
+in vec2 v_texCoord0;
+
+out vec4 o_color;
+
+void main() {
+    vec2 step = 1.0 / textureSize(tex0, 0);
+    float ref = step(0.5 , texture(tex0, v_texCoord0).r);
+    vec4 outc = vec4(-1.0, -1.0, 0.0, 1.0);
+
+    float contour = 0.0;
+    for (int y = -1; y <= 1; ++y) {
+        for (int x = -1; x <= 1; ++x) {
+            float smp = step(0.5, texture(tex0, v_texCoord0 + vec2(x,y) * step).r);
+            if (smp != ref) {
+                contour = 1.0;
+            }
+        }
+    }
+
+    o_color = vec4(contour, contour, contour, 1.0);
+}

orx-jumpflood/src/main/resources/shaders/gl3/threshold.frag

@@ -0,0 +1,13 @@
+#version 330 core
+
+uniform sampler2D tex0;
+in vec2 v_texCoord0;
+uniform float threshold;
+out vec4 o_color;
+
+void main() {
+    float ref = step(threshold , dot( vec3(1.0/3.0), texture(tex0, v_texCoord0).rgb ));
+
+
+    o_color = vec4(ref, ref, ref, 1.0);
+}