add GameCamera: support map and hud

1 files changed, 152 insertions, 0 deletions

diff --git a/core/src/ch/asynk/tankontank/screens/GameCamera.java b/core/src/ch/asynk/tankontank/screens/GameCamera.java
new file mode 100644
index 0000000..14c308b
--- /dev/null
+++ b/core/src/ch/asynk/tankontank/screens/GameCamera.java
@@ -0,0 +1,152 @@
+package ch.asynk.tankontank.screens;
+
+import com.badlogic.gdx.Gdx;
+
+import com.badlogic.gdx.graphics.OrthographicCamera;
+
+import com.badlogic.gdx.math.Rectangle;
+import com.badlogic.gdx.math.Matrix4;
+import com.badlogic.gdx.math.Vector3;
+import com.badlogic.gdx.math.MathUtils;
+
+public class GameCamera extends OrthographicCamera
+{
+    private static final float ZEROF = 0.01f;
+
+    // private int screenWidth;
+    // private int screenHeight;
+    private float zoomOut;
+    private float zoomIn;
+    private float widthFactor;
+    private float heightFactor;
+    private Rectangle screen;
+    private Matrix4 hudMatrix;
+    private Matrix4 hudInvProjMatrix;
+
+    public GameCamera(float virtualWidth, float virtualHeight, float zoomOut, float zoomIn)
+    {
+        super(virtualWidth, virtualHeight);
+        this.zoomOut = zoomOut;
+        this.zoomIn = zoomIn;
+        this.screen = new Rectangle();
+        this.hudMatrix = new Matrix4();
+        this.hudInvProjMatrix = new Matrix4();
+    }
+
+    public void updateViewport(int screenWidth, int screenHeight)
+    {
+        // this.screenWidth = screenWidth;
+        // this.screenHeight = screenHeight;
+
+        float viewportAspect = (viewportWidth / viewportHeight);
+        float aspect = (screenWidth / (float) screenHeight);
+
+        if ((viewportAspect - aspect) < ZEROF) {
+            screen.width = (screenHeight * viewportAspect);
+            screen.height = screenHeight;
+            screen.x = ((screenWidth - screen.width) / 2f);
+            screen.y = 0f;
+        } else {
+            screen.width = screenWidth;
+            screen.height = (screenWidth / viewportAspect);
+            screen.x = 0f;
+            screen.y = ((screenHeight - screen.height) / 2f);
+        }
+
+        Gdx.gl.glViewport((int)screen.x, (int)screen.y, (int)screen.width, (int)screen.height);
+
+        this.widthFactor = (viewportWidth / screenWidth);
+        this.heightFactor = (viewportHeight / screenHeight);
+
+        clampZoom();
+        update(true);
+        hudMatrix.set(combined);
+        hudMatrix.setToOrtho2D(0, 0, screen.width, screen.height);
+        hudInvProjMatrix.set(hudMatrix);
+        Matrix4.inv(hudInvProjMatrix.val);
+    }
+
+    public Matrix4 getHudMatrix()
+    {
+        return hudMatrix;
+    }
+
+    public int getHudWidth()
+    {
+        return (int) screen.width;
+    }
+
+    public int getHudHeight()
+    {
+        return (int) screen.height;
+    }
+
+    public void centerOnWorld()
+    {
+        position.set((viewportWidth / 2f), (viewportHeight / 2f), 0f);
+    }
+
+    public void zoom(float dz)
+    {
+        // TODO adapt screen -> glViewport
+        zoom += dz;
+        clampZoom();
+        update(true);
+    }
+
+    public void translate(float dx, float dy)
+    {
+        float deltaX = (dx * zoom * widthFactor);
+        float deltaY = (dy * zoom * heightFactor);
+        translate(deltaX, -deltaY, 0);
+        clampPosition();
+        update(true);
+    }
+
+    public void clampZoom()
+    {
+        zoom = MathUtils.clamp(zoom, zoomIn, zoomOut);
+        clampPosition();
+    }
+
+    public void clampPosition()
+    {
+        float cx = (viewportWidth * zoom);
+        float cy = (viewportHeight * zoom);
+
+        if ((viewportWidth - cx) > ZEROF) {
+            cx /= 2f;
+            position.x = MathUtils.clamp(position.x, cx, (viewportWidth - cx));
+        } else
+            position.x = (viewportWidth / 2f);
+
+        if ((viewportHeight - cy) > ZEROF) {
+            cy /= 2f;
+            position.y = MathUtils.clamp(position.y, cy, (viewportHeight - cy));
+        } else
+            position.y = (viewportHeight / 2f);
+    }
+
+    public void debug()
+    {
+        System.err.println(String.format("VIEWPORT: %dx%d", (int)viewportWidth, (int)viewportHeight));
+        System.err.println(String.format("  SCREEN: %d;%d %dx%d", (int)screen.x, (int)screen.y, (int)screen.width, (int)screen.height));
+        System.err.println("MATRIX:" + combined.toString());
+    }
+
+    public void unproject(int x, int y, Vector3 v)
+    {
+        unproject(v.set(x, y, 0), screen.x, screen.y, screen.width, screen.height);
+    }
+
+    public void unprojectHud(float x, float y, Vector3 v)
+    {
+        x = x - screen.x;
+        y = Gdx.graphics.getHeight() - y - 1;
+        y = y - screen.y;
+        v.x = (2 * x) / screen.width - 1;
+        v.y = (2 * y) / screen.height - 1;
+        v.z = 2 * v.z - 1;
+        v.prj(hudInvProjMatrix);
+    }
+}