Java tutorial
/******************************************************************************* * Copyright 2011 See AUTHORS file. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. ******************************************************************************/ package com.badlogic.gdx.utils.viewport; import com.badlogic.gdx.ApplicationListener; import com.badlogic.gdx.Gdx; import com.badlogic.gdx.Screen; import com.badlogic.gdx.graphics.Camera; import com.badlogic.gdx.math.Matrix4; import com.badlogic.gdx.math.Rectangle; import com.badlogic.gdx.math.Vector2; import com.badlogic.gdx.math.Vector3; import com.badlogic.gdx.math.collision.Ray; import com.badlogic.gdx.scenes.scene2d.utils.ScissorStack; /** Manages a {@link Camera} and determines how world coordinates are mapped to and from the screen. * @author Daniel Holderbaum * @author Nathan Sweet */ public abstract class Viewport { private Camera camera; private float worldWidth, worldHeight; private int screenX, screenY, screenWidth, screenHeight; private final Vector3 tmp = new Vector3(); /** Calls {@link #apply(boolean)} with false. */ public void apply() { apply(false); } /** Applies the viewport to the camera and sets the glViewport. * @param centerCamera If true, the camera position is set to the center of the world. */ public void apply(boolean centerCamera) { Gdx.gl.glViewport(screenX, screenY, screenWidth, screenHeight); camera.viewportWidth = worldWidth; camera.viewportHeight = worldHeight; if (centerCamera) camera.position.set(worldWidth / 2, worldHeight / 2, 0); camera.update(); } /** Calls {@link #update(int, int, boolean)} with false. */ public final void update(int screenWidth, int screenHeight) { update(screenWidth, screenHeight, false); } /** Configures this viewport's screen bounds using the specified screen size and calls {@link #apply(boolean)}. Typically called * from {@link ApplicationListener#resize(int, int)} or {@link Screen#resize(int, int)}. * <p> * The default implementation only calls {@link #apply(boolean)}. */ public void update(int screenWidth, int screenHeight, boolean centerCamera) { apply(centerCamera); } /** Transforms the specified screen coordinate to world coordinates. * @return The vector that was passed in, transformed to world coordinates. * @see Camera#unproject(Vector3) */ public Vector2 unproject(Vector2 screenCoords) { tmp.set(screenCoords.x, screenCoords.y, 1); camera.unproject(tmp, screenX, screenY, screenWidth, screenHeight); screenCoords.set(tmp.x, tmp.y); return screenCoords; } /** Transforms the specified world coordinate to screen coordinates. * @return The vector that was passed in, transformed to screen coordinates. * @see Camera#project(Vector3) */ public Vector2 project(Vector2 worldCoords) { tmp.set(worldCoords.x, worldCoords.y, 1); camera.project(tmp, screenX, screenY, screenWidth, screenHeight); worldCoords.set(tmp.x, tmp.y); return worldCoords; } /** Transforms the specified screen coordinate to world coordinates. * @return The vector that was passed in, transformed to world coordinates. * @see Camera#unproject(Vector3) */ public Vector3 unproject(Vector3 screenCoords) { camera.unproject(screenCoords, screenX, screenY, screenWidth, screenHeight); return screenCoords; } /** Transforms the specified world coordinate to screen coordinates. * @return The vector that was passed in, transformed to screen coordinates. * @see Camera#project(Vector3) */ public Vector3 project(Vector3 worldCoords) { camera.project(worldCoords, screenX, screenY, screenWidth, screenHeight); return worldCoords; } /** @see Camera#getPickRay(float, float, float, float, float, float) */ public Ray getPickRay(float screenX, float screenY) { return camera.getPickRay(screenX, screenY, this.screenX, this.screenY, screenWidth, screenHeight); } /** @see ScissorStack#calculateScissors(Camera, float, float, float, float, Matrix4, Rectangle, Rectangle) */ public void calculateScissors(Matrix4 batchTransform, Rectangle area, Rectangle scissor) { ScissorStack.calculateScissors(camera, screenX, screenY, screenWidth, screenHeight, batchTransform, area, scissor); } /** Transforms a point to real screen coordinates (as opposed to OpenGL ES window coordinates), where the origin is in the top * left and the the y-axis is pointing downwards. */ public Vector2 toScreenCoordinates(Vector2 worldCoords, Matrix4 transformMatrix) { tmp.set(worldCoords.x, worldCoords.y, 0); tmp.mul(transformMatrix); camera.project(tmp); tmp.y = Gdx.graphics.getHeight() - tmp.y; worldCoords.x = tmp.x; worldCoords.y = tmp.y; return worldCoords; } public Camera getCamera() { return camera; } public void setCamera(Camera camera) { this.camera = camera; } public float getWorldWidth() { return worldWidth; } /** The virtual width of this viewport in world coordinates. This width is scaled to the viewport's screen width. */ public void setWorldWidth(float worldWidth) { this.worldWidth = worldWidth; } public float getWorldHeight() { return worldHeight; } /** The virtual height of this viewport in world coordinates. This height is scaled to the viewport's screen height. */ public void setWorldHeight(float worldHeight) { this.worldHeight = worldHeight; } public void setWorldSize(float worldWidth, float worldHeight) { this.worldWidth = worldWidth; this.worldHeight = worldHeight; } public int getScreenX() { return screenX; } /** Sets the viewport's offset from the left edge of the screen. This is typically set by {@link #update(int, int, boolean)}. */ public void setScreenX(int screenX) { this.screenX = screenX; } public int getScreenY() { return screenY; } /** Sets the viewport's offset from the bottom edge of the screen. This is typically set by {@link #update(int, int, boolean)}. */ public void setScreenY(int screenY) { this.screenY = screenY; } public int getScreenWidth() { return screenWidth; } /** Sets the viewport's width in screen coordinates. This is typically set by {@link #update(int, int, boolean)}. */ public void setScreenWidth(int screenWidth) { this.screenWidth = screenWidth; } public int getScreenHeight() { return screenHeight; } /** Sets the viewport's height in screen coordinates. This is typically set by {@link #update(int, int, boolean)}. */ public void setScreenHeight(int screenHeight) { this.screenHeight = screenHeight; } /** Sets the viewport's position in screen coordinates. This is typically set by {@link #update(int, int, boolean)}. */ public void setScreenPosition(int screenX, int screenY) { this.screenX = screenX; this.screenY = screenY; } /** Sets the viewport's size in screen coordinates. This is typically set by {@link #update(int, int, boolean)}. */ public void setScreenSize(int screenWidth, int screenHeight) { this.screenWidth = screenWidth; this.screenHeight = screenHeight; } /** Sets the viewport's bounds in screen coordinates. This is typically set by {@link #update(int, int, boolean)}. */ public void setScreenBounds(int screenX, int screenY, int screenWidth, int screenHeight) { this.screenX = screenX; this.screenY = screenY; this.screenWidth = screenWidth; this.screenHeight = screenHeight; } /** Returns the left gutter (black bar) width in screen coordinates. */ public int getLeftGutterWidth() { return screenX; } /** Returns the right gutter (black bar) x in screen coordinates. */ public int getRightGutterX() { return screenX + screenWidth; } /** Returns the right gutter (black bar) width in screen coordinates. */ public int getRightGutterWidth() { return Gdx.graphics.getWidth() - (screenX + screenWidth); } /** Returns the bottom gutter (black bar) height in screen coordinates. */ public int getBottomGutterHeight() { return screenY; } /** Returns the top gutter (black bar) y in screen coordinates. */ public int getTopGutterY() { return screenY + screenHeight; } /** Returns the top gutter (black bar) height in screen coordinates. */ public int getTopGutterHeight() { return Gdx.graphics.getHeight() - (screenY + screenHeight); } }