我一直在试图弄清楚如何移植 these tutorials 的第 2 章.
该代码仅产生黑屏，我不明白为什么。没有产生任何错误。
package modern.opengl;
import java.awt.image.BufferedImage;
import java.awt.image.DataBufferByte;
import java.io.File;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.FloatBuffer;
import java.nio.ShortBuffer;
import java.util.logging.FileHandler;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import org.lwjgl.LWJGLException;
import org.lwjgl.input.Keyboard;
import org.lwjgl.input.Mouse;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;
import static org.lwjgl.opengl.GL11.*;
import static org.lwjgl.opengl.GL12.GL_BGR;
import static org.lwjgl.opengl.GL12.GL_CLAMP_TO_EDGE;
import static org.lwjgl.opengl.GL13.*;
import static org.lwjgl.opengl.GL15.*;
import static org.lwjgl.opengl.GL20.*;
import org.lwjgl.util.Timer;
public class Lesson01 {
public static final Logger logger = Logger.getLogger(Lesson01.class.getName());
static {
try {
logger.addHandler(new FileHandler("errors.log", true));
} catch (IOException ex) {
logger.log(Level.WARNING, ex.toString(), ex);
}
}
private int displayWidth;
private int displayHeight;
private String displayTitle;
private int vertexBuffer;
private int elementBuffer;
private int texture0;
private int texture1;
private int program;
private int uniformFadeFactor;
private int uniformTexture0;
private int uniformTexture1;
private int attributePosition;
private float fadeFactor;
private Timer timer;
public static void main(String[] args) {
Lesson01 lesson01 = null;
try {
lesson01 = new Lesson01();
lesson01.setup();
lesson01.run();
} catch (Exception ex) {
logger.log(Level.SEVERE, ex.toString(), ex);
} finally {
if (lesson01 != null) {
lesson01.teardown();
}
}
}
public Lesson01() {
timer = new Timer();
timer.resume();
displayWidth = 400;
displayHeight = 300;
displayTitle = "Lesson 01";
}
public void makeResources() throws Exception {
float[] vertexBufferDataArray = {-1.0f, -1.0f, 1.0f, -1.0f, -1.0f, 1.0f, 1.0f, 1.0f};
FloatBuffer vertexBufferData = ByteBuffer.allocateDirect(vertexBufferDataArray.length * 4).asFloatBuffer();
vertexBufferData.put(vertexBufferDataArray);
vertexBufferData.rewind();
vertexBuffer = glGenBuffers();
glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer);
glBufferData(GL_ARRAY_BUFFER, vertexBufferData, GL_STATIC_DRAW);
short[] elementBufferDataArray = {0, 1, 2, 3};
ShortBuffer elementBufferData = ByteBuffer.allocateDirect(elementBufferDataArray.length * 2).asShortBuffer();
elementBufferData.put(elementBufferDataArray);
elementBufferData.rewind();
elementBuffer = glGenBuffers();
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, elementBuffer);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, elementBufferData, GL_STATIC_DRAW);
texture0 = makeTexture("hello1.png");
texture1 = makeTexture("hello2.png");
if (texture0 == 0 || texture1 == 0) {
throw new Exception("Failed to allocate textures!");
}
String vertexShaderSource =
"#version 110 \n"
+ "attribute vec2 position; \n"
+ "varying vec2 texcoord; \n"
+ "void main() \n"
+ "{ \n"
+ "gl_Position = vec4(position, 0.0, 1.0); \n"
+ "texcoord = position * vec2(0.5) + vec2(0.5); \n"
+ "} \n";
int vertexShader = glCreateShader(GL_VERTEX_SHADER);
glShaderSource(vertexShader, vertexShaderSource);
glCompileShader(vertexShader);
if (glGetShader(vertexShader, GL_COMPILE_STATUS) == 0) {
logger.log(Level.SEVERE, glGetShaderInfoLog(vertexShader, 10240));
throw new Exception("Failed to compile vertex shader!");
}
String fragmentShaderSource =
"#version 110 \n"
+ "uniform float fade_factor; \n"
+ "uniform sampler2D textures[2]; \n"
+ "varying vec2 texcoord; \n"
+ "void main() \n"
+ "{ \n"
+ " gl_FragColor = mix( \n"
+ " texture2D(textures[0], texcoord), \n"
+ " texture2D(textures[1], texcoord), \n"
+ " fade_factor \n"
+ " ); \n"
+ "} \n";
int fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(fragmentShader, fragmentShaderSource);
glCompileShader(fragmentShader);
if (glGetShader(fragmentShader, GL_COMPILE_STATUS) == 0) {
logger.log(Level.SEVERE, glGetShaderInfoLog(fragmentShader, 10240));
throw new Exception("Failed to compule vertex shader!");
}
program = glCreateProgram();
glAttachShader(program, vertexShader);
glAttachShader(program, fragmentShader);
glLinkProgram(program);
if (glGetProgram(program, GL_LINK_STATUS) == 0) {
logger.log(Level.SEVERE, glGetProgramInfoLog(program, 10240));
throw new Exception("Failed to link shader program.");
}
uniformFadeFactor = glGetUniformLocation(program, "fade_factor");
uniformTexture0 = glGetUniformLocation(program, "textures[0]");
uniformTexture1 = glGetUniformLocation(program, "textures[1]");
attributePosition = glGetAttribLocation(program, "position");
}
public void setup() throws LWJGLException, Exception {
Display.setDisplayMode(new DisplayMode(displayWidth, displayHeight));
Display.setFullscreen(false);
Display.setTitle(displayTitle);
Display.create();
Keyboard.create();
Mouse.create();
makeResources();
}
public void teardown() {
Mouse.destroy();
Keyboard.destroy();
Display.destroy();
}
public void run() {
while (!Display.isCloseRequested()) {
Timer.tick();
if (Display.isVisible()) {
fadeFactor = (float) (Math.sin(timer.getTime()) * 0.5 + 0.5);
render();
} else {
if (Display.isDirty()) {
render();
}
try {
Thread.sleep(100);
} catch (InterruptedException ex) {
// Pass
}
}
Display.update();
Display.sync(60);
}
}
public void render() {
glUseProgram(program);
glUniform1f(uniformFadeFactor, fadeFactor);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, texture0);
glUniform1i(uniformTexture0, 0);
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, texture1);
glUniform1i(uniformTexture1, 1);
glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer);
glVertexAttribPointer(attributePosition, 2, GL_FLOAT, false, 8, 0);
glEnableVertexAttribArray(attributePosition);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, elementBuffer);
glDrawElements(GL_TRIANGLE_STRIP, 4, GL_SHORT, 0);
glDisableVertexAttribArray(attributePosition);
}
public static int makeTexture(String filename) throws IOException {
BufferedImage bufferedImage = ImageIO.read(new File(filename));
byte[] textureBufferArray = ((DataBufferByte) (bufferedImage.getRaster().getDataBuffer())).getData();
ByteBuffer textureBuffer = ByteBuffer.allocateDirect(textureBufferArray.length);
textureBuffer.put(textureBufferArray);
textureBuffer.rewind();
int textureId = glGenTextures();
glBindTexture(GL_TEXTURE_2D, textureId);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexImage2D(
GL_TEXTURE_2D,
0,
GL_RGB8,
bufferedImage.getWidth(),
bufferedImage.getHeight(),
0,
GL_BGR,
GL_UNSIGNED_BYTE,
textureBuffer
);
return textureId;
}
}
最佳答案
我猜你已经找到了。 添加选项 -Dorg.lwjgl.util.Debug=true 我尝试了同样的事情，我认为错误在于该行 glDrawElements(GL_TRIANGLE_STRIP, 4, GL_SHORT, 0); 从规范http://www.opengl.org/sdk/docs/man/xhtml/glDrawElements.xml ，类型不能为 GL_SHORT。
关于java - LWJGL代码产生黑屏，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/9089020/