[orx-integral-image] Pad source image for npot inputs. Add demo

orx-integral-image/README.md

@@ -2,62 +2,3 @@
 
 CPU and GPU-based implementation for integral images (summed area tables)
 
-#### Usage
-
-```kotlin
-val image = colorBuffer( ... )
-image.shadow.download()
-val integralImage = IntegralImage.fromColorBufferShadow(image.shadow)
-
-// -- the sum for a given area can be queried using
-val sum = integralImage.sum(IntRectangle(20, 20, 100, 100))
-```
-
-## Fast Integral Image
-
-Since v0.0.20 orx-integral-image comes with `FastIntegralImage` which calculates integral images fully on the GPU.
-
-```kotlin
-import org.openrndr.application
-import org.openrndr.color.ColorRGBa
-import org.openrndr.draw.*
-import org.openrndr.extra.integralimage.*
-
-fun main(args: Array<String>) = application {
-    configure {
-        width = 1024
-        height = 1024
-    }
-    program {
-        val fii = FastIntegralImage()
-        val target = colorBuffer(1024, 512, 1.0, ColorFormat.RGBa, ColorType.FLOAT32)
-        val rt = renderTarget(1024, 512) {
-            colorBuffer()
-        }
-        extend {
-            drawer.background(ColorRGBa.PINK)
-            drawer.isolatedWithTarget(rt) {
-                drawer.ortho(rt)
-                drawer.background(ColorRGBa.BLACK)
-                drawer.fill = ColorRGBa.PINK.shade(1.0)
-                drawer.circle(mouse.position, 128.0)
-            }
-            fii.apply(rt.colorBuffer(0),target)
-
-            // -- here we sample from the integral image
-            drawer.shadeStyle = shadeStyle {
-                fragmentTransform = """
-                    float w = 128.0;
-                    vec2 step = 1.0 / textureSize(image, 0);
-                    vec4 t11 = texture(image, va_texCoord0 + step * vec2(w,w));
-                    vec4 t01 = texture(image, va_texCoord0 + step * vec2(-w,w));
-                    vec4 t00 = texture(image, va_texCoord0 + step * vec2(-w,-w));
-                    vec4 t10 = texture(image, va_texCoord0 + step * vec2(w,-w));
-                    x_fill = (t11 - t01 - t10 + t00) / (w*w);
-                """.trimIndent()
-            }
-            drawer.image(target)
-        }
-    }
-}
-```

orx-integral-image/src/demo/kotlin/DemoFII01.kt

@@ -0,0 +1,42 @@
+import org.openrndr.application
+import org.openrndr.color.ColorRGBa
+import org.openrndr.draw.*
+import org.openrndr.extra.integralimage.*
+
+fun main() = application {
+    configure {
+        width = 720
+        height = 720
+    }
+    program {
+        val fii = FastIntegralImage()
+        val target = colorBuffer(width, height, 1.0, ColorFormat.RGBa, ColorType.FLOAT32)
+        val rt = renderTarget(width, height) {
+            colorBuffer()
+        }
+        extend {
+            drawer.clear(ColorRGBa.PINK)
+            drawer.isolatedWithTarget(rt) {
+                drawer.ortho(rt)
+                drawer.clear(ColorRGBa.BLACK)
+                drawer.fill = ColorRGBa.PINK.shade(1.0)
+                drawer.circle(mouse.position, 128.0)
+            }
+            fii.apply(rt.colorBuffer(0), target)
+
+            // -- here we sample from the integral image
+            drawer.shadeStyle = shadeStyle {
+                fragmentTransform = """
+                    float w = 64.0;
+                    vec2 step = 1.0 / vec2(textureSize(image, 0));
+                    vec4 t11 = texture(image, va_texCoord0 + step * vec2(w+1.0,w+1.0));
+                    vec4 t01 = texture(image, va_texCoord0 + step * vec2(-w,w+1.0));
+                    vec4 t00 = texture(image, va_texCoord0 + step * vec2(-w,-w));
+                    vec4 t10 = texture(image, va_texCoord0 + step * vec2(w+1.0,-w));
+                    x_fill = (t11 - t01 - t10 + t00) / ((2.0 * w +1.0) * (2.0 * w + 1.0));
+                """.trimIndent()
+            }
+            drawer.image(target)
+        }
+    }
+}

orx-integral-image/src/main/kotlin/FastIntegralImage.kt

@@ -5,27 +5,43 @@ import org.openrndr.extra.fx.blend.Passthrough
 
 import org.openrndr.math.Vector2
 import org.openrndr.resourceUrl
+import org.openrndr.shape.IntRectangle
 import org.openrndr.shape.Rectangle
+import kotlin.math.ceil
+import kotlin.math.log
 
 
-class FastIntegralImageFilter : Filter(filterShaderFromUrl(resourceUrl(
-        "/shaders/gl3/integral-image.frag"
-))) {
+internal class FastIntegralImageFilter : Filter(
+    filterShaderFromUrl(
+        resourceUrl(
+            "/shaders/gl3/integral-image.frag"
+        )
+    )
+) {
     var passIndex: Int by parameters
     var passDirection: Vector2 by parameters
     var sampleCount: Int by parameters
     var sampleCountBase: Int by parameters
 }
 
-class FastIntegralImage : Filter(filterShaderFromUrl(resourceUrl(
-        "/shaders/gl3/integral-image.frag"
-))) {
+/**
+ * Compute an integral image for the source image
+ */
+class FastIntegralImage : Filter(
+    filterShaderFromUrl(
+        resourceUrl(
+            "/shaders/gl3/integral-image.frag"
+        )
+    )
+) {
     private val passthrough = Passthrough()
 
     var intermediate: ColorBuffer? = null
-    val filter = FastIntegralImageFilter()
+    var sourceCropped: ColorBuffer? = null
+    var targetPadded: ColorBuffer? = null
+    private val filter = FastIntegralImageFilter()
 
-    private fun sampleCounts(size:Int, sampleCountBase:Int) : List<Int> {
+    private fun sampleCounts(size: Int, sampleCountBase: Int): List<Int> {
         var remainder = size
         val sampleCounts = mutableListOf<Int>()
         while (remainder > 0) {
@@ -41,40 +57,90 @@ class FastIntegralImage : Filter(filterShaderFromUrl(resourceUrl(
 
     override fun apply(source: Array<ColorBuffer>, target: Array<ColorBuffer>, clip: Rectangle?) {
         require(clip == null)
+        require(source[0].isEquivalentTo(target[0], ignoreFormat = true, ignoreType = true))
+
+        val npotx = ceil(log(source[0].effectiveWidth.toDouble(), 2.0)).toInt()
+        val npoty = ceil(log(source[0].effectiveHeight.toDouble(), 2.0)).toInt()
+
+        val recWidth = 1 shl npotx
+        val recHeight = 1 shl npoty
+
+        if (recWidth != source[0].effectiveWidth || recHeight != source[0].effectiveHeight) {
+            if (sourceCropped?.effectiveWidth != recWidth || sourceCropped?.effectiveHeight != recHeight) {
+                sourceCropped?.destroy()
+                targetPadded?.destroy()
+            }
+
+            if (sourceCropped == null) {
+                sourceCropped = source[0].createEquivalent(width = recWidth, height = recHeight, contentScale = 1.0)
+                targetPadded = target[0].createEquivalent(
+                    width = (recWidth / target[0].contentScale).toInt(),
+                    height = (recHeight / target[0].contentScale).toInt(),
+                    contentScale = 1.0
+                )
+            }
+            source[0].copyTo(sourceCropped!!,
+                sourceRectangle = IntRectangle(0, 0, source[0].effectiveWidth, source[0].effectiveHeight),
+                targetRectangle = IntRectangle(0, recHeight-source[0].effectiveHeight, source[0].effectiveWidth, source[0].effectiveHeight)
+            )
+        }
+
         val sampleCountBase = 16
-        val xSampleCounts = sampleCounts(source[0].width, sampleCountBase)
-        val ySampleCounts = sampleCounts(source[0].height, sampleCountBase)
+        val xSampleCounts = sampleCounts(recWidth, sampleCountBase)
+        val ySampleCounts = sampleCounts(recHeight, sampleCountBase)
 
         val li = intermediate
-        if (li == null || (li.width != source[0].width || li.height != source[0].height)) {
+        if (li == null || (li.effectiveWidth != recWidth || li.effectiveHeight != recHeight)) {
             intermediate?.destroy()
-            intermediate = colorBuffer(source[0].width, source[0].height, 1.0, ColorFormat.RGBa, ColorType.FLOAT32)
+            intermediate = colorBuffer(recWidth, recHeight, 1.0, ColorFormat.RGBa, ColorType.FLOAT32)
         }
 
-        val targets = arrayOf(target, arrayOf(intermediate!!))
+        val targets = arrayOf(if (targetPadded == null) target else arrayOf(targetPadded!!), arrayOf(intermediate!!))
 
         var targetIndex = 0
 
         filter.sampleCountBase = sampleCountBase
 
+        /*
+        Perform horizontal steps
+         */
         filter.passDirection = Vector2.UNIT_X
         for (pass in xSampleCounts.indices) {
             filter.sampleCount = xSampleCounts[pass]
             filter.passIndex = pass
-            filter.apply( if (pass == 0) source else targets[targetIndex%2], targets[(targetIndex+1)%2])
+            filter.apply(
+                if (pass == 0) {
+                    if (sourceCropped == null) source else arrayOf(sourceCropped!!)
+                } else targets[targetIndex % 2], targets[(targetIndex + 1) % 2]
+            )
             targetIndex++
         }
 
+
+        /*
+        Perform vertical steps
+         */
         filter.passDirection = Vector2.UNIT_Y
         for (pass in ySampleCounts.indices) {
             filter.sampleCount = ySampleCounts[pass]
             filter.passIndex = pass
-            filter.apply( targets[targetIndex%2], targets[(targetIndex+1)%2])
+            filter.apply(targets[targetIndex % 2], targets[(targetIndex + 1) % 2])
             targetIndex++
         }
 
-        if (targetIndex%2 == 1) {
+        // this is a bit wasteful
+        if (targetIndex % 2 == 1) {
             passthrough.apply(targets[1], targets[0])
         }
+
+        /*
+        When the source is not a power of two we copy from the padded target to the target
+         */
+        if (targetPadded != null) {
+            targetPadded!!.copyTo(target[0],
+                sourceRectangle = IntRectangle(0, recHeight-source[0].effectiveHeight, source[0].effectiveWidth, source[0].effectiveHeight),
+                targetRectangle = IntRectangle(0, 0, source[0].effectiveWidth, source[0].effectiveHeight)
+            )
+        }
     }
 }

orx-integral-image/src/main/resources/shaders/gl3/integral-image.frag

@@ -1,5 +1,3 @@
-#version 330 core
-
 uniform sampler2D tex0;
 in vec2 v_texCoord0;
 out vec4 o_color;
@@ -11,16 +9,18 @@ uniform vec2 passDirection;
 
 
 void main() {
-    vec2 passOffset = vec2(pow(sampleCountBase, passIndex)) * (1.0/textureSize(tex0, 0)) * passDirection;
+    vec2 passOffset = vec2(
+        pow(float(sampleCountBase),
+        float(passIndex))) * (1.0 / vec2(textureSize(tex0, 0))
+    ) * passDirection;
 
     vec2 uv0 = v_texCoord0;
+//    uv0.y = 1.0 - uv0.y;
     vec4 result = vec4(0.0);
     for (int i = 0; i < sampleCount; ++i) {
-        vec2 readUV = v_texCoord0 - vec2(i *passOffset);
+        vec2 readUV = v_texCoord0 - vec2(float(i) * passOffset);
         float factor = step(0.0, readUV.x) * step(0.0, readUV.y);
         result += factor * texture(tex0, readUV);
     }
-
     o_color = result;
-
 }