Added jump flood

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

@@ -0,0 +1,81 @@
+package org.openrndr.extra.jumpfill
+
+import org.openrndr.draw.*
+import org.openrndr.filter.filterShaderFromUrl
+import org.openrndr.math.Matrix44
+import org.openrndr.resourceUrl
+
+class EncodePoints:  Filter(filterShaderFromUrl(resourceUrl("/shaders/gl3/encode-points.frag")))
+class JumpFlood: Filter(filterShaderFromUrl(resourceUrl("/shaders/gl3/jumpflood.frag"))) {
+    var maxSteps: Int by parameters
+    var step: Int by parameters
+}
+
+val encodePoints by lazy { EncodePoints() }
+val jumpFlood by lazy { JumpFlood() }
+
+/** [points] is square and power of 2 */
+fun jumpFlood(points:ColorBuffer, coordinates:List<ColorBuffer>) {
+    encodePoints.apply(points, coordinates[0])
+    val exp = Math.ceil(Math.log(points.width.toDouble()) / Math.log(2.0)).toInt()
+    for (i in 0 until exp) {
+        jumpFlood.step = i
+        jumpFlood.apply(coordinates[i % 2], coordinates[(i + 1) % 2])
+
+    }
+
+}
+
+fun jumpFlood(drawer: Drawer, points:ColorBuffer): ColorBuffer {
+
+    val dimension = Math.max(points.width, points.height)
+    val exp = Math.ceil(Math.log(dimension.toDouble()) / Math.log(2.0)).toInt()
+    val squareDim = Math.pow(2.0, exp.toDouble()).toInt()
+
+    val rt = renderTarget(squareDim, squareDim) {
+        colorBuffer()
+    }
+
+    val coordinates =
+            listOf(colorBuffer(squareDim, squareDim, type = ColorType.FLOAT32),
+                    colorBuffer(squareDim, squareDim, type = ColorType.FLOAT32))
+
+    drawer.isolatedWithTarget(rt) {
+        drawer.ortho(rt)
+        drawer.view = Matrix44.IDENTITY
+        drawer.model = Matrix44.IDENTITY
+        drawer.image(points)
+    }
+
+    jumpFlood(rt.colorBuffer(0), coordinates)
+
+//    encodePoints.apply(rt.colorBuffer(0), coordinates[0])
+//
+//
+//    for (i in 0 until exp) {
+//        jumpFlood.step = i
+//        jumpFlood.apply(coordinates[i % 2], coordinates[(i + 1) % 2])
+//
+//    }
+
+    val final = renderTarget(points.width, points.height) {
+        colorBuffer(type = ColorType.FLOAT32)
+    }
+
+    drawer.isolatedWithTarget(final) {
+        drawer.ortho(final)
+        drawer.view = Matrix44.IDENTITY
+        drawer.model = Matrix44.IDENTITY
+        drawer.image(coordinates[exp%2])
+
+    }
+
+    rt.colorBuffer(0).destroy()
+    rt.detachColorBuffers()
+    rt.destroy()
+
+    val fcb = final.colorBuffer(0)
+    final.detachColorBuffers()
+    final.destroy()
+    return fcb
+}

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

@@ -0,0 +1,16 @@
+#version 330 core
+
+uniform sampler2D tex0;
+in vec2 v_texCoord0;
+
+out vec4 o_color;
+
+void main() {
+    float ref = texture(tex0, v_texCoord0).r;
+    vec4 outc = vec4(-1.0, -1.0, 0.0, 1.0);
+
+    if (ref > 0.5) {
+        outc.xy = v_texCoord0.xy;
+    }
+    o_color = outc;
+}

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

@@ -0,0 +1,39 @@
+#version 330 core
+in vec2 v_texCoord0;
+
+uniform sampler2D tex0;
+uniform int maxSteps;
+uniform int step;
+
+out vec4 o_color;
+void main() {
+
+    float stepwidth = 1.0 / pow(2.0, step+1);
+
+    float bestDistance = 9999.0;
+    vec2 bestCoord = vec2(-1.0);
+    vec2 bestColor = vec2(-1.0);
+
+    vec2 is = vec2(1.0) / textureSize(tex0, 0);
+
+    float found = 0.0;
+    for (int y = -1; y <= 1; ++y) {
+        for (int x = -1; x <= 1; ++x) {
+            vec2 sampleCoord = v_texCoord0 + vec2(stepwidth) * vec2(x,y);
+            vec4 data = texture( tex0, sampleCoord);
+            vec2 seedCoord = data.xy;
+            vec2 seedColor = data.zw;
+            float dist = length(seedCoord - v_texCoord0);
+            if ((seedCoord.x >= 0.0 || seedCoord.y >= 0.0) && dist < bestDistance)
+            {
+                found = 1.0;
+                bestDistance = dist;
+                bestCoord = seedCoord;
+                bestColor = seedColor;
+            }
+        }
+    }
+
+    o_color = vec4(bestCoord, found, 1.0);
+
+}