[orx-compositor] Add .use demo (#127)

2020-06-19 19:01:40 +02:00
parent 1ca0e2288c
commit 7c324079e2
1 changed files with 90 additions and 0 deletions
--- a/orx-compositor/src/demo/kotlin/DemoUse01.kt
+++ b/orx-compositor/src/demo/kotlin/DemoUse01.kt
@@ -0,0 +1,90 @@
+import org.openrndr.application
+import org.openrndr.color.ColorRGBa
+import org.openrndr.color.rgb
+import org.openrndr.extensions.SingleScreenshot
+import org.openrndr.extra.compositor.*
+import org.openrndr.extra.fx.blend.Add
+import org.openrndr.extra.fx.blur.ApproximateGaussianBlur
+import org.openrndr.extra.fx.color.ColorCorrection
+import kotlin.random.Random
+
+/**
+ * Compositor demo of `use`, which makes it possible to
+ * use the color buffer of a previous layer.
+ *
+ * This program draws a series of concentric rings, most of them gray,
+ * 10% are pink.
+ *
+ * In a second layer we reuse that image with rings, applying an extreme
+ * color correction to make everything black except the pink rings,
+ * then apply a strong blur and finally compose it over the original
+ * image using blend mode Add.
+ *
+ * The result is an sharp image of gray rings with glowing pink rings.
+ *
+ * Note: see also orx-fx Bloom()
+ *
+ */
+
+// Toggle to see the difference between a simple blur and multilayer bloom
+const val effectEnabled = true
+
+fun main() = application {
+    configure {
+        width = 900
+        height = 900
+    }
+
+    program {
+        // -- this block is for automation purposes only
+        if (System.getProperty("takeScreenshot") == "true") {
+            extend(SingleScreenshot()) {
+                this.outputFile = System.getProperty("screenshotPath")
+            }
+        }
+
+        val composite = compose {
+            val circles = layer {
+                draw {
+                    drawer.stroke = null
+                    val rnd = Random(frameCount / 100 + 1)
+                    for (i in 18 downTo 0) {
+                        drawer.fill = if (rnd.nextDouble() < 0.1)
+                            ColorRGBa.PINK.shade(Random.nextDouble(0.88, 1.0))
+                        else
+                            rgb(rnd.nextInt(6) / 15.0)
+
+                        drawer.circle(drawer.bounds.center, 50.0 + i * 20)
+                    }
+                }
+                // A. To see how the plain blur looks like
+                if (!effectEnabled) {
+                    post(ApproximateGaussianBlur()) {
+                        sigma = 25.0
+                        window = 25
+                    }
+                }
+            }
+            // B. This is the bloom effect
+            if (effectEnabled) {
+                layer {
+                    use(circles) // <-- use the previous layer as starting point
+                    post(ColorCorrection()) {
+                        brightness = -0.3
+                        contrast = 0.8
+                    }
+                    post(ApproximateGaussianBlur()) {
+                        sigma = 25.0
+                        window = 25
+                    }
+                    blend(Add())
+                }
+            }
+        }
+
+        extend {
+            drawer.clear(rgb(0.2))
+            composite.draw(drawer)
+        }
+    }
+}