591 lines
18 KiB
Java
591 lines
18 KiB
Java
package org.lwjgl.test.opengl.sprites;
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import org.lwjgl.BufferUtils;
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import org.lwjgl.LWJGLException;
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import org.lwjgl.Sys;
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import org.lwjgl.input.Keyboard;
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import org.lwjgl.input.Mouse;
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import org.lwjgl.opengl.*;
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import java.awt.image.BufferedImage;
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import java.awt.image.Raster;
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import java.io.IOException;
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import java.nio.ByteBuffer;
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import java.nio.FloatBuffer;
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import java.util.Random;
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import javax.imageio.ImageIO;
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import static org.lwjgl.opengl.EXTTransformFeedback.*;
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import static org.lwjgl.opengl.GL11.*;
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import static org.lwjgl.opengl.GL15.*;
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import static org.lwjgl.opengl.GL20.*;
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import static org.lwjgl.opengl.GL30.*;
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import static org.lwjgl.opengl.GL32.*;
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/**
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* Sprite rendering demo. In this version we're doing the animation
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* computations on the GPU, using transform feedback and a vertex
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* shader, then rendering is performed in 2 passes, with depth testing
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* enabled:
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* 1) Sprites are rendered front-to-back, opaque fragments only, blending is disabled.
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* 2) Sprites are rendered back-to-front, transparent fragments only, blending is enabled.
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* Sorting is free, because we're animating double the amount of sprites rendered, the
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* first batch is sorted f2b, the second is sorted b2f. Ordering is achieved by modifying
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* the z-axis position of the sprites in the vertex shader.
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*
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* @author Spasi
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* @since 18/3/2011
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*/
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public final class SpriteShootout2P {
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private static final int SCREEN_WIDTH = 800;
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private static final int SCREEN_HEIGHT = 600;
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private static final int ANIMATION_TICKS = 60;
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private boolean run = true;
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private boolean render = true;
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private boolean colorMask = true;
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private boolean animate = true;
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private boolean smooth;
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private boolean vsync;
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private int ballSize = 42;
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private int ballCount = 100 * 1000;
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private SpriteRenderer renderer;
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// OpenGL stuff
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private int texID;
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private int texBigID;
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private int texSmallID;
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private SpriteShootout2P() {
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}
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public static void main(String[] args) {
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try {
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new SpriteShootout2P().start();
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} catch (LWJGLException e) {
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e.printStackTrace();
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}
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}
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private void start() throws LWJGLException {
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try {
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initGL();
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renderer = new SpriteRendererTF();
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updateBalls(ballCount);
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run();
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} catch (Throwable t) {
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t.printStackTrace();
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} finally {
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destroy();
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}
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}
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private void initGL() throws LWJGLException {
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Display.setLocation((Display.getDisplayMode().getWidth() - SCREEN_WIDTH) / 2,
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(Display.getDisplayMode().getHeight() - SCREEN_HEIGHT) / 2);
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Display.setDisplayMode(new DisplayMode(SCREEN_WIDTH, SCREEN_HEIGHT));
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Display.setTitle("Sprite Shootout 2-pass");
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Display.create(new PixelFormat(0, 24, 0));
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//Display.create(new PixelFormat(), new ContextAttribs(4, 1).withProfileCompatibility(true).withDebug(true));
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//AMDDebugOutput.glDebugMessageCallbackAMD(new AMDDebugOutputCallback());
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final ContextCapabilities caps = GLContext.getCapabilities();
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if ( !(caps.OpenGL30 || (caps.OpenGL20 && caps.GL_EXT_transform_feedback)) )
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throw new RuntimeException("OpenGL 3.0 or 2.0 + EXT_transform_feedback is required for this demo.");
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// Setup viewport
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glMatrixMode(GL_PROJECTION);
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glLoadIdentity();
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glOrtho(0, SCREEN_WIDTH, 0, SCREEN_HEIGHT, -1.0, 1.0);
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glMatrixMode(GL_MODELVIEW);
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glLoadIdentity();
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glViewport(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT);
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glClearColor(1.0f, 1.0f, 1.0f, 0.0f);
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// Create textures
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try {
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texSmallID = createTexture("res/ball_sm.png");
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texBigID = createTexture("res/ball.png");
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} catch (IOException e) {
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e.printStackTrace();
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System.exit(-1);
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}
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texID = texBigID;
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// Setup rendering state
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glEnable(GL_BLEND);
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glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
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glEnable(GL_ALPHA_TEST);
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glColorMask(colorMask, colorMask, colorMask, false);
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glDepthMask(true);
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glEnable(GL_DEPTH_TEST);
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glDepthFunc(GL_LESS);
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glClearDepth(1.0f);
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// Setup geometry
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glEnableClientState(GL_VERTEX_ARRAY);
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glEnableClientState(GL_TEXTURE_COORD_ARRAY);
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Util.checkGLError();
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}
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private static int createTexture(final String path) throws IOException {
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final BufferedImage img = ImageIO.read(SpriteShootout2P.class.getClassLoader().getResource(path));
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final int w = img.getWidth();
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final int h = img.getHeight();
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final ByteBuffer buffer = readImage(img);
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final int texID = glGenTextures();
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glBindTexture(GL_TEXTURE_2D, texID);
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glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
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glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
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glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
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glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
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glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, w, h, 0, GL_BGRA, GL_UNSIGNED_BYTE, buffer);
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return texID;
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}
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private static ByteBuffer readImage(final BufferedImage img) throws IOException {
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final Raster raster = img.getRaster();
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final int bands = raster.getNumBands();
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final int w = img.getWidth();
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final int h = img.getHeight();
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final int size = w * h * bands;
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final byte[] pixels = new byte[size];
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raster.getDataElements(0, 0, w, h, pixels);
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final ByteBuffer pbuffer = BufferUtils.createByteBuffer(size);
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if ( bands == 4 ) {
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for ( int i = 0; i < (w * h * 4); i += 4 ) {
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// Pre-multiply alpha
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final float a = unpackUByte01(pixels[i + 3]);
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pbuffer.put(packUByte01(unpackUByte01(pixels[i + 2]) * a));
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pbuffer.put(packUByte01(unpackUByte01(pixels[i + 1]) * a));
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pbuffer.put(packUByte01(unpackUByte01(pixels[i + 0]) * a));
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pbuffer.put(pixels[i + 3]);
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}
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} else if ( bands == 3 ) {
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for ( int i = 0; i < (w * h * 3); i += 3 ) {
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pbuffer.put(pixels[i + 2]);
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pbuffer.put(pixels[i + 1]);
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pbuffer.put(pixels[i + 0]);
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}
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} else
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pbuffer.put(pixels, 0, size);
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pbuffer.flip();
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return pbuffer;
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}
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private static float unpackUByte01(final byte x) {
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return (x & 0xFF) / 255.0f;
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}
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private static byte packUByte01(final float x) {
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return (byte)(x * 255.0f);
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}
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private void updateBalls(final int count) {
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System.out.println("NUMBER OF BALLS: " + count);
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renderer.updateBalls(ballCount);
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}
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private void run() {
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long startTime = System.currentTimeMillis() + 5000;
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long fps = 0;
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long time = Sys.getTime();
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final int ticksPerUpdate = (int)(Sys.getTimerResolution() / ANIMATION_TICKS);
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renderer.render(false, true, 0);
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while ( run ) {
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Display.processMessages();
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handleInput();
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glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
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final long currTime = Sys.getTime();
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final int delta = (int)(currTime - time);
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if ( smooth || delta >= ticksPerUpdate ) {
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renderer.render(render, animate, delta);
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time = currTime;
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} else
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renderer.render(render, false, 0);
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Display.update(false);
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//Display.sync(60);
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if ( startTime > System.currentTimeMillis() ) {
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fps++;
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} else {
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long timeUsed = 5000 + (startTime - System.currentTimeMillis());
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startTime = System.currentTimeMillis() + 5000;
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System.out.println("FPS: " + (Math.round(fps / (timeUsed / 1000.0) * 10) / 10.0) + ", Balls: " + ballCount);
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fps = 0;
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}
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}
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}
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private void handleInput() {
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if ( Display.isCloseRequested() )
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run = false;
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while ( Keyboard.next() ) {
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if ( Keyboard.getEventKeyState() )
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continue;
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switch ( Keyboard.getEventKey() ) {
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case Keyboard.KEY_1:
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case Keyboard.KEY_2:
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case Keyboard.KEY_3:
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case Keyboard.KEY_4:
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case Keyboard.KEY_5:
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case Keyboard.KEY_6:
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case Keyboard.KEY_7:
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case Keyboard.KEY_8:
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case Keyboard.KEY_9:
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case Keyboard.KEY_0:
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ballCount = 1 << (Keyboard.getEventKey() - Keyboard.KEY_1);
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updateBalls(ballCount);
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break;
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case Keyboard.KEY_ADD:
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case Keyboard.KEY_SUBTRACT:
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int mult;
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if ( Keyboard.isKeyDown(Keyboard.KEY_LSHIFT) || Keyboard.isKeyDown(Keyboard.KEY_RSHIFT) ) {
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mult = 1000;
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if ( Keyboard.isKeyDown(Keyboard.KEY_LCONTROL) || Keyboard.isKeyDown(Keyboard.KEY_RCONTROL) )
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mult *= 5;
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} else if ( Keyboard.isKeyDown(Keyboard.KEY_LMENU) || Keyboard.isKeyDown(Keyboard.KEY_RMENU) )
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mult = 100;
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else if ( Keyboard.isKeyDown(Keyboard.KEY_LCONTROL) || Keyboard.isKeyDown(Keyboard.KEY_RCONTROL) )
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mult = 10;
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else
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mult = 1;
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if ( Keyboard.getEventKey() == Keyboard.KEY_SUBTRACT )
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mult = -mult;
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ballCount += mult * 100;
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if ( ballCount <= 0 )
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ballCount = 1;
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updateBalls(ballCount);
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break;
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case Keyboard.KEY_ESCAPE:
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run = false;
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break;
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case Keyboard.KEY_A:
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animate = !animate;
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System.out.println("Animation is now " + (animate ? "on" : "off") + ".");
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break;
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case Keyboard.KEY_C:
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colorMask = !colorMask;
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glColorMask(colorMask, colorMask, colorMask, false);
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System.out.println("Color mask is now " + (colorMask ? "on" : "off") + ".");
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// Disable alpha test when color mask is off, else we get no benefit.
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if ( colorMask ) {
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glEnable(GL_BLEND);
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glEnable(GL_ALPHA_TEST);
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} else {
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glDisable(GL_BLEND);
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glDisable(GL_ALPHA_TEST);
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}
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break;
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case Keyboard.KEY_R:
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render = !render;
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System.out.println("Rendering is now " + (render ? "on" : "off") + ".");
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break;
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case Keyboard.KEY_S:
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smooth = !smooth;
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System.out.println("Smooth animation is now " + (smooth ? "on" : "off") + ".");
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break;
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case Keyboard.KEY_T:
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if ( texID == texBigID ) {
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texID = texSmallID;
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ballSize = 16;
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} else {
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texID = texBigID;
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ballSize = 42;
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}
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renderer.updateBallSize();
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glBindTexture(GL_TEXTURE_2D, texID);
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System.out.println("Now using the " + (texID == texBigID ? "big" : "small") + " texture.");
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break;
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case Keyboard.KEY_V:
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vsync = !vsync;
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Display.setVSyncEnabled(vsync);
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System.out.println("VSYNC is now " + (vsync ? "enabled" : "disabled") + ".");
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break;
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}
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}
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while ( Mouse.next() ) ;
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}
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private void destroy() {
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Display.destroy();
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}
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private abstract class SpriteRenderer {
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protected int progID;
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protected void createPrograms(final int vshID) {
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// Opaque pass
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final int fshID = glCreateShader(GL_FRAGMENT_SHADER);
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glShaderSource(fshID, "uniform sampler2D COLOR_MAP;\n" +
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"void main(void) {\n" +
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" gl_FragColor = texture2D(COLOR_MAP, gl_PointCoord);\n" +
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"}");
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glCompileShader(fshID);
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if ( glGetShader(fshID, GL_COMPILE_STATUS) == GL_FALSE ) {
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System.out.println(glGetShaderInfoLog(fshID, glGetShader(fshID, GL_INFO_LOG_LENGTH)));
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throw new RuntimeException("Failed to compile fragment shader.");
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}
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progID = glCreateProgram();
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glAttachShader(progID, vshID);
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glAttachShader(progID, fshID);
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glLinkProgram(progID);
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if ( glGetProgram(progID, GL_LINK_STATUS) == GL_FALSE ) {
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System.out.println(glGetProgramInfoLog(progID, glGetProgram(progID, GL_INFO_LOG_LENGTH)));
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throw new RuntimeException("Failed to link shader program.");
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}
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glUseProgram(progID);
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glUniform1i(glGetUniformLocation(progID, "COLOR_MAP"), 0);
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updateBallSize();
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glEnableClientState(GL_VERTEX_ARRAY);
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}
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public void updateBallSize() {
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glPointSize(ballSize);
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}
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protected abstract void updateBalls(final int count);
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protected abstract void render(boolean render, boolean animate, int delta);
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}
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private class SpriteRendererTF extends SpriteRenderer {
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private int progIDTF;
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private int ballSizeLoc;
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private int deltaLoc;
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private int[] tfVBO = new int[2];
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private int currVBO;
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private int depthVBO;
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private int depthLoc;
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SpriteRendererTF() {
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System.out.println("Shootout Implementation: TF GPU animation & 2-pass rendering");
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// Transform-feedback program
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int vshID = glCreateShader(GL_VERTEX_SHADER);
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glShaderSource(vshID, "#version 130\n" +
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"const float WIDTH = " + SCREEN_WIDTH + ";\n" +
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"const float HEIGHT = " + SCREEN_HEIGHT + ";\n" +
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"uniform float ballSize;\n" + // ballSize / 2
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"uniform float delta;\n" +
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"void main(void) {\n" +
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" vec4 anim = gl_Vertex;\n" +
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" anim.xy = anim.xy + anim.zw * delta;\n" +
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" vec2 animC = clamp(anim.xy, vec2(ballSize), vec2(WIDTH - ballSize, HEIGHT - ballSize));\n" +
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" if ( anim.x != animC.x ) anim.z = -anim.z;\n" +
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" if ( anim.y != animC.y ) anim.w = -anim.w;\n" +
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" gl_Position = vec4(animC, anim.zw);\n" +
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"}");
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glCompileShader(vshID);
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if ( glGetShader(vshID, GL_COMPILE_STATUS) == GL_FALSE ) {
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System.out.println(glGetShaderInfoLog(vshID, glGetShader(vshID, GL_INFO_LOG_LENGTH)));
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throw new RuntimeException("Failed to compile vertex shader.");
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}
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progIDTF = glCreateProgram();
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glAttachShader(progIDTF, vshID);
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glTransformFeedbackVaryings(progIDTF, new CharSequence[] { "gl_Position" }, GL_SEPARATE_ATTRIBS);
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glLinkProgram(progIDTF);
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if ( glGetProgram(progIDTF, GL_LINK_STATUS) == GL_FALSE ) {
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System.out.println(glGetProgramInfoLog(progIDTF, glGetProgram(progIDTF, GL_INFO_LOG_LENGTH)));
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throw new RuntimeException("Failed to link shader program.");
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}
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glUseProgram(progIDTF);
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ballSizeLoc = glGetUniformLocation(progIDTF, "ballSize");
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deltaLoc = glGetUniformLocation(progIDTF, "delta");
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glUniform1f(ballSizeLoc, ballSize * 0.5f);
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// -----------------
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vshID = glCreateShader(GL_VERTEX_SHADER);
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glShaderSource(vshID, "#version 130\n" +
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"in float depth;\n" +
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"void main(void) {\n" +
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" gl_Position = gl_ModelViewProjectionMatrix * vec4(gl_Vertex.xy, depth, gl_Vertex.w);\n" +
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"}");
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glCompileShader(vshID);
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if ( glGetShader(vshID, GL_COMPILE_STATUS) == GL_FALSE ) {
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System.out.println(glGetShaderInfoLog(vshID, glGetShader(vshID, GL_INFO_LOG_LENGTH)));
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throw new RuntimeException("Failed to compile vertex shader.");
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}
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createPrograms(vshID);
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depthLoc = glGetAttribLocation(progID, "depth");
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// -----------------
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}
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public void updateBallSize() {
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glUseProgram(progIDTF);
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glUniform1f(ballSizeLoc, ballSize * 0.5f);
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super.updateBallSize();
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}
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public void updateBalls(final int count) {
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// Depth data
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final FloatBuffer depths = BufferUtils.createFloatBuffer(count * 2);
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final float depthStep = 1.9f / count;
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float depth = Float.parseFloat("0x1.fffffep-1");
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// Front-to-back
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for ( int i = 0; i < count; i++ ) {
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depths.put(depth);
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depth -= depthStep;
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}
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// Back-to-front
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for ( int i = 0; i < count; i++ )
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depths.put(depths.get(count - 1 - i));
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depths.flip();
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if ( depthVBO != 0 )
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glDeleteBuffers(depthVBO);
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depthVBO = glGenBuffers();
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glBindBuffer(GL_ARRAY_BUFFER, depthVBO);
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glBufferData(GL_ARRAY_BUFFER, depths, GL_STATIC_DRAW);
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glEnableVertexAttribArray(depthLoc);
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glVertexAttribPointer(depthLoc, 1, GL_FLOAT, false, 0, 0);
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|
|
|
// Animation data
|
|
|
|
final FloatBuffer transform = BufferUtils.createFloatBuffer(count * 2 * 4);
|
|
// Front-to-back
|
|
final Random random = new Random();
|
|
for ( int i = 0; i < count; i++ ) {
|
|
transform.put((int)(random.nextFloat() * (SCREEN_WIDTH - ballSize) + ballSize * 0.5f));
|
|
transform.put((int)(random.nextFloat() * (SCREEN_HEIGHT - ballSize) + ballSize * 0.5f));
|
|
transform.put(random.nextFloat() * 0.4f - 0.2f);
|
|
transform.put(random.nextFloat() * 0.4f - 0.2f);
|
|
}
|
|
// Back-to-front
|
|
for ( int i = 0; i < count; i++ ) {
|
|
final int offset = (count - 1 - i) * 4;
|
|
transform.put(transform.get(offset + 0));
|
|
transform.put(transform.get(offset + 1));
|
|
transform.put(transform.get(offset + 2));
|
|
transform.put(transform.get(offset + 3));
|
|
}
|
|
transform.flip();
|
|
|
|
if ( tfVBO[0] != 0 ) {
|
|
for ( int i = 0; i < tfVBO.length; i++ )
|
|
glDeleteBuffers(tfVBO[i]);
|
|
}
|
|
|
|
for ( int i = 0; i < tfVBO.length; i++ ) {
|
|
tfVBO[i] = glGenBuffers();
|
|
glBindBuffer(GL_TRANSFORM_FEEDBACK_BUFFER, tfVBO[i]);
|
|
glBufferData(GL_TRANSFORM_FEEDBACK_BUFFER, transform, GL_STATIC_DRAW);
|
|
}
|
|
|
|
glBindBuffer(GL_ARRAY_BUFFER, tfVBO[0]);
|
|
glVertexPointer(2, GL_FLOAT, (4 * 4), 0);
|
|
}
|
|
|
|
public void render(final boolean render, final boolean animate, final int delta) {
|
|
if ( animate ) {
|
|
glDisableVertexAttribArray(depthLoc);
|
|
|
|
final int vbo = currVBO;
|
|
currVBO = 1 - currVBO;
|
|
|
|
glUseProgram(progIDTF);
|
|
glUniform1f(deltaLoc, delta);
|
|
|
|
glBindBuffer(GL_ARRAY_BUFFER, tfVBO[vbo]);
|
|
glVertexPointer(4, GL_FLOAT, 0, 0);
|
|
|
|
glEnable(GL_RASTERIZER_DISCARD);
|
|
if ( GLContext.getCapabilities().OpenGL30 ) {
|
|
glBindBufferBase(GL_TRANSFORM_FEEDBACK_BUFFER, 0, tfVBO[1 - vbo]);
|
|
|
|
glBeginTransformFeedback(GL_POINTS);
|
|
glDrawArrays(GL_POINTS, 0, ballCount * 2);
|
|
glEndTransformFeedback();
|
|
} else {
|
|
glBindBufferBaseEXT(GL_TRANSFORM_FEEDBACK_BUFFER_EXT, 0, tfVBO[1 - vbo]);
|
|
|
|
glBeginTransformFeedbackEXT(GL_POINTS);
|
|
glDrawArrays(GL_POINTS, 0, ballCount * 2);
|
|
glEndTransformFeedbackEXT();
|
|
}
|
|
glDisable(GL_RASTERIZER_DISCARD);
|
|
|
|
glUseProgram(progID);
|
|
glVertexPointer(2, GL_FLOAT, (4 * 4), 0);
|
|
|
|
glEnableVertexAttribArray(depthLoc);
|
|
}
|
|
|
|
if ( render ) {
|
|
// Render front-to-back opaque pass
|
|
glAlphaFunc(GL_EQUAL, 1.0f);
|
|
glDisable(GL_BLEND);
|
|
glDrawArrays(GL_POINTS, 0, ballCount);
|
|
glEnable(GL_BLEND);
|
|
|
|
// Render back-to-front transparent pass
|
|
glAlphaFunc(GL_GREATER, 0.0f); // Fragments with alpha == 1.0 are early-depth-rejected.
|
|
glDepthMask(false);
|
|
glDrawArrays(GL_POINTS, ballCount, ballCount);
|
|
glDepthMask(true);
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
} |