UI : add Scissors

1 files changed, 67 insertions, 0 deletions

diff --git a/core/src/ch/asynk/gdx/boardgame/ui/Scissors.java b/core/src/ch/asynk/gdx/boardgame/ui/Scissors.java
new file mode 100644
index 0000000..096b883
--- /dev/null
+++ b/core/src/ch/asynk/gdx/boardgame/ui/Scissors.java
@@ -0,0 +1,67 @@
+package ch.asynk.gdx.boardgame.ui;
+
+import com.badlogic.gdx.graphics.Camera;
+import com.badlogic.gdx.graphics.g2d.Batch;
+import com.badlogic.gdx.math.Rectangle;
+import com.badlogic.gdx.scenes.scene2d.utils.ScissorStack;
+
+import ch.asynk.gdx.boardgame.utils.IterableArray;
+
+public class Scissors
+{
+    private static IterableArray<Rectangle> array = new IterableArray<Rectangle>(5);
+
+    private static Camera camera;
+    private static Batch batch;
+
+    public static void clear()
+    {
+        array.clear();
+    }
+
+    public static void invalidate()
+    {
+        for (int i = 0; i < array.size(); i++)
+            array.replace(null, i);
+    }
+
+    public static void register(Camera _camera, Batch _batch)
+    {
+        camera = _camera;
+        batch = _batch;
+        invalidate();
+    }
+
+    public static int compute(int idx, Rectangle area)
+    {
+        if (idx < 0) {
+            array.add(compute(area));
+            return array.size() - 1;
+        } else {
+            array.replace(compute(area), idx);
+            return idx;
+        }
+    }
+
+    public static Rectangle get(int idx, Rectangle area)
+    {
+        Rectangle r = array.get(idx);
+        if (r == null) {
+            array.replace(compute(area), idx);
+            r = array.get(idx);
+        }
+        return r;
+    }
+
+    public static Rectangle compute(Rectangle area)
+    {
+        Rectangle scissor = new Rectangle();
+        compute(area, scissor);
+        return scissor;
+    }
+
+    public static void compute(Rectangle area, Rectangle scissor)
+    {
+        ScissorStack.calculateScissors(camera, batch.getTransformMatrix(), area, scissor);
+    }
+}