[orx-camera] add defaults() to Camera2D and OrbitalCamera.

Add DemoCamera2DManual01.kt

orx-camera/src/commonMain/kotlin/Camera2D.kt

@@ -13,7 +13,7 @@ import org.openrndr.math.Vector2
 import org.openrndr.math.transforms.buildTransform
 
 /**
- * The [Camera2D] extension enables panning, rotating and zooming the view
+ * The [Camera2D] extension enables panning, rotating, and zooming the view
  * with the mouse:
  * - left click and drag to **pan**
  * - right click and drag to **rotate**
@@ -59,6 +59,17 @@ class Camera2D : Extension, ChangeEvents {
         }
     }
 
+    /**
+     * Reinitialize the camera to its default state, where no transformations
+     * (such as rotation, translation, or scaling) are applied. It also sets the `dirty` flag to `true`,
+     * indicating that the camera's state has been modified and needs to be updated or rendered accordingly.
+     */
+    fun defaults() {
+        view = Matrix44.IDENTITY
+        rotationCenter = Vector2.ZERO
+        dirty = true
+    }
+
     /**
      * Configures the mouse interaction events for controlling the camera view and handling
      * transformations such as translation, rotation, and scaling via mouse inputs.
@@ -71,8 +82,7 @@ class Camera2D : Extension, ChangeEvents {
             rotationCenter = it.position
 
             if (it.button == MouseButton.CENTER) {
-                view = Matrix44.IDENTITY
-                dirty = true
+                defaults()
             }
         }
         mouse.dragged.listen {

orx-camera/src/commonMain/kotlin/OrbitalCamera.kt

@@ -65,6 +65,24 @@ class OrbitalCamera(
     var orthoNear = -1000.0
     var orthoFar = 1000.0
 
+    // Defaults
+    val eyeDefault = eye.copy()
+    val lookAtDefault = lookAt.copy()
+    val fovDefault = fov
+    val magnitudeDefault = magnitude
+
+    /**
+     * Reinitialize the camera to its initial state.
+     *
+     * @param instant whether the rotation is applied immediately; if false, it interpolates over time (default is false)
+     */
+    fun defaults(instant: Boolean = false) {
+        panTo(lookAtDefault, instant)
+        rotateTo(eyeDefault, instant)
+        zoomTo(fovDefault, instant)
+        scaleTo(magnitudeDefault, instant)
+    }
+
     /**
      * Sets the view for the orbital camera by updating the look-at position, spherical coordinates,
      * and field of view (FOV). This method initializes both the target and current states of these properties.

orx-camera/src/jvmDemo/kotlin/DemoCamera2D02.kt

@@ -21,8 +21,8 @@ fun main() = application {
             colorBuffer()
             depthBuffer()
         }
-        // Create camera and apply an initial transformation
-        // so the origin is no longer in the top left corner.
+        // Create a camera and apply an initial transformation
+        // so the origin is no longer in the top-left corner.
         val cam = Camera2D()
         cam.view *= transform {
             translate(width * 0.5, height * 1.0)

orx-camera/src/jvmDemo/kotlin/DemoCamera2DManual01.kt

@@ -1,26 +1,17 @@
-import org.openrndr.PresentationMode
 import org.openrndr.application
 import org.openrndr.color.ColorRGBa
-import org.openrndr.draw.isolatedWithTarget
-import org.openrndr.draw.loadFont
-import org.openrndr.draw.renderTarget
-import org.openrndr.extra.camera.Camera2D
 import org.openrndr.extra.camera.Camera2DManual
-import org.openrndr.math.Vector2
-import org.openrndr.math.transforms.transform
-import org.openrndr.shape.Rectangle
-import kotlin.math.sin
 
 /**
  * Demonstrate the use of `Camera2DManual` for manual camera control.
  *
  * The application is configured with a 720x720 window size. Within the program, a custom camera (`Camera2DManual`)
- * is initialized and used to create isolated drawing scopes. The `isolated` method is utilized to overlay different
+ * is initialized and used to create isolated drawing scopes. The `isolated` method is used to overlay different
  * drawing operations while maintaining individual camera states, ensuring proper transformations for specific elements.
  *
- * A pink circle is drawn at the center of the canvas with varying radii using isolated and non-isolated camera states.
- * The outermost and innermost circles are affected by the `Camera2DManual` isolated scope, while the middle circle
- * is outside of the camera's isolated scope, creating a layered visual effect.
+ * Three circles are drawn on the canvas: a small pink one, a medium white one and a large pink one.
+ * Only the pink ones are affected by the interactive `Camera2DManual`, while the middle white circle is outside
+ * the camera's isolated scope.
  */
 fun main() = application {
     configure {

orx-camera/src/jvmDemo/kotlin/DemoCamera2DManual02.kt

@@ -0,0 +1,69 @@
+import org.openrndr.application
+import org.openrndr.color.ColorRGBa
+import org.openrndr.extra.camera.Camera2DManual
+import org.openrndr.extra.noise.shapes.uniform
+import org.openrndr.extra.noise.uniform
+import org.openrndr.math.Vector2
+import org.openrndr.math.transforms.transform
+import org.openrndr.shape.Rectangle
+import org.openrndr.shape.contains
+
+/**
+ * Demonstrate the use of `Camera2DManual` to independently translate, scale and rotate one contour
+ * in a collection.
+ *
+ * When the mouse is clicked, the active contour is transformed using the camera view matrix,
+ * then the camera is reset to its default state and whatever shape is under the mouse becomes
+ * the new active contour.
+ *
+ * As the mouse is dragged or its wheel scrolled, the camera is updated, affecting
+ * how the active contour is rendered.
+ */
+fun main() = application {
+    configure {
+        width = 720
+        height = 720
+    }
+
+    program {
+        val camera = Camera2DManual()
+        // Create a mutable list of rectangular contours with random transformations
+        // applied to them. This is the initial state for the contours.
+        val contours = MutableList(16) {
+            Rectangle.fromCenter(Vector2.ZERO, 85.0).contour.transform(
+                transform {
+                    translate(drawer.bounds.uniform())
+                    scale(Double.uniform(0.5, 2.0))
+                    rotate(Double.uniform(0.0, 360.0))
+                }
+            )
+        }
+
+        var activeContour = -1
+        extend {
+            // Draw all contours. The active contour is drawn in pink and
+            // affected by the camera's transformations.
+            contours.forEachIndexed { i, c ->
+                if (i == activeContour) {
+                    camera.isolated {
+                        drawer.fill = ColorRGBa.PINK
+                        drawer.contour(c)
+                    }
+                } else {
+                    drawer.fill = ColorRGBa.GRAY
+                    drawer.contour(c)
+                }
+            }
+        }
+        mouse.buttonDown.listen {
+            // Apply the camera view matrix to the active contour
+            if (activeContour >= 0) contours[activeContour] = contours[activeContour].transform(camera.view)
+
+            // Reset the camera to its default state
+            camera.defaults()
+
+            // Make the contour under the mouse the active contour
+            activeContour = contours.indexOfLast { mouse.position in it }
+        }
+    }
+}

orx-camera/src/jvmDemo/kotlin/DemoOrbitalCamera01.kt

@@ -54,5 +54,10 @@ fun main() = application {
                 drawer.circle(0.0, 0.0, 50.0)
             }
         }
+        keyboard.keyDown.listen {
+            if (it.name == "r") {
+                camera.defaults()
+            }
+        }
     }
 }