Refactor GraphicsContext: implement translation handling and update drawing methods to use translation values

src/main/java/be/seeseemelk/diceos/system/gfx/GraphicsContext.java

@@ -6,7 +6,6 @@ import com.badlogic.gdx.graphics.Texture;
 import com.badlogic.gdx.graphics.g2d.Batch;
 import com.badlogic.gdx.graphics.g2d.BitmapFont;
 import com.badlogic.gdx.graphics.g2d.NinePatch;
-import com.badlogic.gdx.math.Matrix4;
 import com.badlogic.gdx.math.Rectangle;
 import com.badlogic.gdx.scenes.scene2d.utils.ScissorStack;
 import lombok.Getter;
@@ -28,12 +27,17 @@ public class GraphicsContext {
 
     private final Stack<GraphicsState> stateStack = new java.util.Stack<>();
 
+    private int translateX = 0;
+    private int translateY = 0;
+
     private static class GraphicsState {
-        private final Matrix4 transform;
+        private final int translateX;
+        private final int translateY;
         private int scissorCount;
 
-        public GraphicsState(Matrix4 transform, int scissorCount) {
+        public GraphicsState(int translateX, int translateY, int scissorCount) {
-            this.transform = transform.cpy();
+            this.translateX = translateX;
+            this.translateY = translateY;
             this.scissorCount = scissorCount;
         }
     }
@@ -47,7 +51,7 @@ public class GraphicsContext {
      * @param height The height.
      */
     public void draw(NinePatch image, int x, int y, int width, int height) {
-        image.draw(batch, x, getHeight() - height - y, width, height);
+        image.draw(batch, x + translateX, getHeight() - height - (y + translateY), width, height);
     }
 
     /**
@@ -57,7 +61,7 @@ public class GraphicsContext {
      * @param y The y-coordinate.
      */
     public void draw(Texture texture, int x, int y) {
-        draw(texture, x, y, Parameters.DEFAULT);
+        draw(texture, x + translateX, y + translateY, Parameters.DEFAULT);
     }
 
     /**
@@ -69,7 +73,7 @@ public class GraphicsContext {
      */
     public void draw(Texture texture, int x, int y, Parameters params) {
         batch.draw(texture,
-                x, getHeight() - y - texture.getHeight(), texture.getWidth(), texture.getHeight(),
+                x + translateX, getHeight() - (y + translateY) - texture.getHeight(), texture.getWidth(), texture.getHeight(),
                 0, 0, texture.getWidth(), texture.getHeight(),
                 params.flipX, params.flipY);
     }
@@ -81,7 +85,7 @@ public class GraphicsContext {
      * @param y The y coordinate to draw at.
      */
     public void draw(String text, int x, int y) {
-        font.draw(batch, text, x, getHeight() - (y + font.getLineHeight()));
+        font.draw(batch, text, x + translateX, getHeight() - (y + translateY + font.getLineHeight()));
     }
 
     /**
@@ -93,7 +97,7 @@ public class GraphicsContext {
      */
     public void fillRect(int x, int y, int width, int height) {
         var texture = DiceOS.getResourceLoader().loadTexture("system/white.png");
-        batch.draw(texture, x, getHeight() - height - y, width, height); // This is not ideal.
+        batch.draw(texture, x + translateX, getHeight() - height - (y + translateY), width, height);
     }
 
     /**
@@ -114,7 +118,8 @@ public class GraphicsContext {
      * @param y The number of pixels to move down by.
      */
     public void translate(int x, int y) {
-        batch.setTransformMatrix(batch.getTransformMatrix().trn(x, -y, 0));
+        translateX += x;
+        translateY += y;
     }
 
     /**
@@ -123,11 +128,11 @@ public class GraphicsContext {
      * @return The total amount of X-translation.
      */
     public int getXTranslation() {
-        return (int) batch.getTransformMatrix().val[com.badlogic.gdx.math.Matrix4.M03];
+        return translateX;
     }
 
     public int getYTranslation() {
-        return (int) batch.getTransformMatrix().val[com.badlogic.gdx.math.Matrix4.M13];
+        return translateY;
     }
 
     /**
@@ -170,7 +175,7 @@ public class GraphicsContext {
      * The state can later be restored using {@link #restore()}.
      */
     public void save() {
-        stateStack.push(new GraphicsState(batch.getTransformMatrix(), 0));
+        stateStack.push(new GraphicsState(translateX, translateY, 0));
     }
 
     /**
@@ -183,7 +188,8 @@ public class GraphicsContext {
         }
         batch.flush();
         GraphicsState state = stateStack.pop();
-        batch.setTransformMatrix(state.transform);
+        translateX = state.translateX;
+        translateY = state.translateY;
         for (int i = 0; i < state.scissorCount; i++) {
             ScissorStack.popScissors();
         }

src/test/java/be/seeseemelk/diceos/system/gfx/GraphicsContextTest.java

@@ -10,6 +10,7 @@ import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
 import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.Mockito.*;
 
@@ -59,7 +60,8 @@ class GraphicsContextTest {
     @Test
     void testTranslate() {
         gc.translate(10, 20);
-        verify(batch).setTransformMatrix(any(Matrix4.class));
+        assertEquals(10, gc.getXTranslation());
+        assertEquals(20, gc.getYTranslation());
     }
 
     @Test