ImageReducerExample.kt

src/jvmMain/kotlin/afield/examples/four/ImageReducerExample.kt · 96 lines

package afield.examples.four

import afield.graphics.vulkan.Renderer
import afield.graphics.vulkan.targets.RenderTarget
import afield.graphics.texture.LoadedTexture
import afield.graphics.vulkan.util.ImageReducer
import afield.graphics.vulkan.util.Window

class ImageReducerExample

Example demonstrating the usage of ImageReducer utility class.

Shows both the "just do it once" case (runOnce, via ImageReducer.reduceNow) and the "do it every frame" case (runPerFrame, via ImageReducer.installInto).

See the KDoc on afield.graphics.vulkan.util.ImageReducer for the authoritative API, buffer layout, and sampled-texture binding model.

val window = Window("ImageReducer Example")

val renderer = Renderer(window)

fun runOnce()

Example 1: "Just do it once" - synchronous one-shot execution

    fun runOnce() {
        println("\n=== Example 1: One-shot execution ===")

        val texture = LoadedTexture.stubTexture(renderer)
        texture.transferNow()

        // Create the reducer and execute once
        val reducer = ImageReducer(renderer, texture)
        val results = reducer.reduceNow()

        println("Image Reduction Results:")
        println("  Min: [${results.min.joinToString(", ")}]")
        println("  Avg: [${results.avg.joinToString(", ")}]")
        println("  Max: [${results.max.joinToString(", ")}]")

        reducer.cleanup()
        texture.cleanup()
    }

fun runPerFrame()

Example 2: "Do it every frame" - install into RenderTarget.others

    fun runPerFrame() {
        println("\n=== Example 2: Per-frame execution ===")

        val texture = LoadedTexture.stubTexture(renderer)
        texture.transferNow()

        val renderTarget = RenderTarget(renderer)
        renderer.renderList = renderTarget

        // Create reducer and install into render target
        val reducer = ImageReducer(renderer, texture)
        reducer.installInto(renderTarget, "imageStats")

        // Simulate a few frames
        for (frame in 0 until 5) {
            window.pollEvents()
            renderer.render()

            // Read results after frame completes
            val results = reducer.readResults()
            println("Frame $frame - Avg R: ${results.avg[0]}, G: ${results.avg[1]}, B: ${results.avg[2]}")

            if (window.shouldClose()) break
        }

        reducer.cleanup()
        texture.cleanup()
    }

companion object

fun main(args: Array<String>)

        @JvmStatic
        fun main(args: Array<String>) {
            val example = ImageReducerExample()
            try {
                // Run the one-shot example
                example.runOnce()

                // Run the per-frame example
                example.runPerFrame()
            } catch (e: Exception) {
                println("Error running ImageReducer example: ${e.message}")
                e.printStackTrace()
            } finally {
                example.renderer.cleanup()
                example.window.cleanup()
            }
        }
    }
}