Add descriptions to demos

orx-jvm/orx-gui/src/demo/kotlin/DemoSideCanvas01.kt

@@ -2,18 +2,29 @@ import org.openrndr.application
 import org.openrndr.color.ColorRGBa
 import org.openrndr.extra.gui.GUI
 import org.openrndr.extra.gui.GUIAppearance
-import org.openrndr.extra.parameters.*
-import org.openrndr.math.Vector2
+import org.openrndr.extra.parameters.ColorParameter
+import org.openrndr.extra.parameters.Description
+import org.openrndr.extra.parameters.DoubleParameter
 import org.openrndr.panel.elements.draw
 
 
 /**
- * A simple demonstration of a GUI for drawing some circles
+ * Demonstrates the `GUI.enableSideCanvas` feature.
+ *
+ * When set to true, the `GUI` provides a `canvas` property where one can draw.
+ * The size of this canvas is the window size minus the GUI size.
+ *
+ * That's why if we draw a circle at `drawer.width / 2.0` it is centered
+ * on the `canvas`, not on the window.
+ *
+ * This demo sets the window to resizable, so if you resize the window
+ * you should see tha the circle stays at the center of the canvas.
+ *
  */
 fun main() = application {
     configure {
-        width = 800
-        height = 800
+        width = 720
+        height = 720
         windowResizable = true
     }
 
@@ -23,17 +34,11 @@ fun main() = application {
         gui.enableSideCanvas = true
 
         val settings = @Description("Settings") object {
-            @DoubleParameter("radius", 0.0, 100.0)
+            @DoubleParameter("radius", 0.0, 200.0)
             var radius = 50.0
 
-            @Vector2Parameter("position", 0.0, 1.0)
-            var position = Vector2(0.6, 0.5)
-
             @ColorParameter("color")
             var color = ColorRGBa.PINK
-
-            @DoubleListParameter("radii", 5.0, 30.0)
-            var radii = mutableListOf(5.0, 6.0, 8.0, 14.0, 20.0, 30.0)
         }
         gui.add(settings)
         extend(gui)
@@ -42,7 +47,7 @@ fun main() = application {
             val width = drawer.width
             val height = drawer.height
             drawer.fill = settings.color
-            drawer.circle(width/2.0, height/2.0, 100.0)
+            drawer.circle(width / 2.0, height / 2.0, settings.radius)
         }
     }
 }