[orx-image-fit] Tweak demo comments

orx-image-fit/src/jvmDemo/kotlin/DemoImageFit01.kt

@@ -1,15 +1,21 @@
 import org.openrndr.application
 import org.openrndr.color.ColorRGBa
-import org.openrndr.draw.ColorBuffer
-import org.openrndr.draw.isolatedWithTarget
 import org.openrndr.draw.loadFont
-import org.openrndr.draw.renderTarget
+import org.openrndr.drawImage
 import org.openrndr.extra.imageFit.FitMethod
 import org.openrndr.extra.imageFit.imageFit
 import org.openrndr.extra.shapes.primitives.grid
 
 /**
- * Tests `drawer.imageFit()` with all FitMethods for portrait and landscape images.
+ * This program uses `drawer.imageFit()` to draw images using nested grid layout.
+ * The main grid features 4 columns for the `Cover`, `Contain`, `Fill` and `None` fit methods,
+ * and two rows for portrait and landscape images.
+ * Each of those 8 cells feature a 3x3 grid, with cells combining `left`, `center` and `right` alignment
+ * with `top`, `center` and `bottom` alignment.
+ *
+ * The image drawn in each cell is a simple image with a white background and two touching circles:
+ * a pink one and a gray one. In some of the cells part of this image is cropped out (due to the fit method used).
+ * In other cells the image does not fully cover the available area, revealing a dark gray background.
  */
 fun main() = application {
     configure {
@@ -20,44 +26,40 @@ fun main() = application {
     program {
         val font = loadFont("demo-data/fonts/IBMPlexMono-Regular.ttf", 18.0)
 
-        // Create a test image with circles
-        fun makeImage(cols: Int, rows: Int, side: Int = 400): ColorBuffer {
-            val rt = renderTarget(cols * side, rows * side) {
-                colorBuffer()
+        // Create an image with a gray and a pink circle
+        fun makeImage(cols: Int, rows: Int, side: Int = 400) = drawImage(cols * side, rows * side) {
+            clear(ColorRGBa.WHITE)
+            stroke = null
+            bounds.grid(cols, rows).flatten().forEachIndexed { i, it ->
+                fill = if (i % 2 == 0) ColorRGBa.PINK else ColorRGBa.GRAY
+                circle(it.center, side / 2.0)
             }
-            drawer.isolatedWithTarget(rt) {
-                clear(ColorRGBa.WHITE)
-                stroke = null
-                ortho(rt)
-                bounds.grid(cols, rows).flatten().forEachIndexed { i, it ->
-                    fill = if (i % 2 == 0) ColorRGBa.PINK else ColorRGBa.GRAY
-                    circle(it.center, side / 2.0)
-                }
-            }
-            return rt.colorBuffer(0)
         }
 
-        val layouts = mapOf(
+        val namedImages = mapOf(
             "portrait" to makeImage(1, 2),
             "landscape" to makeImage(2, 1)
         )
-        val fitMethods = FitMethod.values()
+        val fitMethods = FitMethod.entries.toTypedArray()
 
-        val grid = drawer.bounds.grid(fitMethods.size, layouts.size, 30.0, 30.0, 30.0, 30.0)
+        val grid = drawer.bounds.grid(fitMethods.size, namedImages.size, 30.0, 30.0, 30.0, 30.0)
 
         extend {
             drawer.fontMap = font
             drawer.stroke = null
             fitMethods.forEachIndexed { y, fitMethod ->
-                layouts.entries.forEachIndexed { x, (layoutName, img) ->
+                namedImages.entries.forEachIndexed { x, (layoutName, img) ->
                     val cell = grid[x][y]
                     // In each grid cell draw 9 fitted images combining
                     // [left, center, right] and [top, center, bottom] alignment
                     val subgrid = cell.grid(3, 3, 0.0, 0.0, 4.0, 4.0)
                     subgrid.forEachIndexed { yy, rects ->
                         rects.forEachIndexed { xx, rect ->
+                            // Draw a dark background
                             drawer.fill = ColorRGBa.WHITE.shade(0.25)
                             drawer.rectangle(rect)
+
+                            // Draw the image using `imageFit`
                             drawer.imageFit(img, rect, xx - 1.0, yy - 1.0, fitMethod)
                         }
                     }

orx-image-fit/src/jvmDemo/kotlin/DemoImageFitSub01.kt

@@ -6,6 +6,17 @@ import org.openrndr.extra.noise.shapes.uniformSub
 import org.openrndr.extra.shapes.primitives.grid
 import kotlin.random.Random
 
+/**
+ * Demonstrates the `imageFitSub()` method, which allows specifying not only a target `Rectangle`,
+ * but also a source `Rectangle`, which is used to set the area of the original image we want to fit
+ * into the target.
+ *
+ * The program also demonstrates the `Rectangle.uniformSub` method, which returns a random sub-rectangle
+ * taking into consideration the minimum and maximum width and height arguments.
+ *
+ * Notice the trick used to generate unique random results changing only once per second by using
+ * the current seconds as an integer seed.
+ */
 fun main() = application {
     configure {
         width = 720