我遇到了一些与OpenGL有关的问题。我得到一个java.lang.RuntimeException：在当前线程中找不到OpenGL上下文。错误。下面我将发布我的堆栈打印输出和我的代码。帮助我对OpenGL的新见。
java.lang.RuntimeException: No OpenGL context found in the current thread.
at org.lwjgl.opengl.GLContext.getCapabilities(GLContext.java:124)
at org.lwjgl.opengl.ARBShaderObjects.glDeleteObjectARB(ARBShaderObjects.java:63)
at mygame.Box.createShader(Box.java:123)
at mygame.Box.<init>(Box.java:36)
at mygame.Main.<init>(Main.java:16)
at mygame.Main.main(Main.java:69)
Main.java
package mygame;
import org.lwjgl.opengl.GL11;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;
import org.lwjgl.util.glu.GLU;
/*
* Sets up the Display, the GL context, and runs the main game
loop.
*
*/
public class Main{
private boolean done=false; //game runs until done is set to true
private Box box = new Box();
public Main(){
init();
while(!done){
if(Display.isCloseRequested())
done=true;
render();
Display.update();
}
Display.destroy();
}
private void render(){
GL11.glClear(GL11.GL_COLOR_BUFFER_BIT |
GL11.GL_DEPTH_BUFFER_BIT);
GL11.glLoadIdentity();
box.draw();
}
private void init(){
int w=1024;
int h=768;
try{
Display.setDisplayMode(new DisplayMode(w, h));
Display.setVSyncEnabled(true);
Display.setTitle("Shader Setup");
Display.create();
}catch(Exception e){
System.out.println("Error setting up display");
System.exit(0);
}
GL11.glViewport(0,0,w,h);
GL11.glMatrixMode(GL11.GL_PROJECTION);
GL11.glLoadIdentity();
GLU.gluPerspective(45.0f, ((float)w/(float)h),0.1f,100.0f);
GL11.glMatrixMode(GL11.GL_MODELVIEW);
GL11.glLoadIdentity();
GL11.glShadeModel(GL11.GL_SMOOTH);
GL11.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
GL11.glClearDepth(1.0f);
GL11.glEnable(GL11.GL_DEPTH_TEST);
GL11.glDepthFunc(GL11.GL_LEQUAL);
GL11.glHint(GL11.GL_PERSPECTIVE_CORRECTION_HINT,
GL11.GL_NICEST);
}
public static void main(String[] args){
new Main();
}
}
Box.java
package mygame;
import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.InputStreamReader;
import org.lwjgl.opengl.ARBFragmentShader;
import org.lwjgl.opengl.ARBShaderObjects;
import org.lwjgl.opengl.ARBVertexShader;
import org.lwjgl.opengl.GL11;
/**
* The vertex and fragment shaders are setup when the box object is
* constructed. They are applied to the GL state prior to the box
* being drawn, and released from that state after drawing.
*/
public class Box {
/*
* if the shaders are setup ok we can use shaders, otherwise we just
* use default settings
*/
private boolean useShader;
/*
* program shader, to which is attached a vertex and fragment shaders.
* They are set to 0 as a check because GL will assign unique int
* values to each
*/
private int program=0;
public Box(){
int vertShader = 0, fragShader = 0;
try {
vertShader = createShader("shaders/screen.vert",ARBVertexShader.GL_VERTEX_SHADER_ARB);
fragShader = createShader("shaders/screen.frag",ARBFragmentShader.GL_FRAGMENT_SHADER_ARB);
}
catch(Exception exc) {
exc.printStackTrace();
return;
}
finally {
if(vertShader == 0 || fragShader == 0)
return;
}
program = ARBShaderObjects.glCreateProgramObjectARB();
if(program == 0)
return;
/*
* if the vertex and fragment shaders setup sucessfully,
* attach them to the shader program, link the sahder program
* (into the GL context I suppose), and validate
*/
ARBShaderObjects.glAttachObjectARB(program, vertShader);
ARBShaderObjects.glAttachObjectARB(program, fragShader);
ARBShaderObjects.glLinkProgramARB(program);
if (ARBShaderObjects.glGetObjectParameteriARB(program, ARBShaderObjects.GL_OBJECT_LINK_STATUS_ARB) == GL11.GL_FALSE) {
System.err.println(getLogInfo(program));
return;
}
ARBShaderObjects.glValidateProgramARB(program);
if (ARBShaderObjects.glGetObjectParameteriARB(program, ARBShaderObjects.GL_OBJECT_VALIDATE_STATUS_ARB) == GL11.GL_FALSE) {
System.err.println(getLogInfo(program));
return;
}
useShader = true;
}
/*
* If the shader was setup succesfully, we use the shader. Otherwise
* we run normal drawing code.
*/
public void draw(){
if(useShader)
ARBShaderObjects.glUseProgramObjectARB(program);
GL11.glLoadIdentity();
GL11.glTranslatef(0.0f, 0.0f, -10.0f);
GL11.glColor3f(1.0f, 1.0f, 1.0f);//white
GL11.glBegin(GL11.GL_QUADS);
GL11.glVertex3f(-1.0f, 1.0f, 0.0f);
GL11.glVertex3f(1.0f, 1.0f, 0.0f);
GL11.glVertex3f(1.0f, -1.0f, 0.0f);
GL11.glVertex3f(-1.0f, -1.0f, 0.0f);
GL11.glEnd();
//release the shader
if(useShader)
ARBShaderObjects.glUseProgramObjectARB(0);
}
/*
* With the exception of syntax, setting up vertex and fragment shaders
* is the same.
* @param the name and path to the vertex shader
*/
private int createShader(String filename, int shaderType) throws Exception {
int shader = 0;
try {
shader = ARBShaderObjects.glCreateShaderObjectARB(shaderType);
if(shader == 0)
return 0;
ARBShaderObjects.glShaderSourceARB(shader, readFileAsString(filename));
ARBShaderObjects.glCompileShaderARB(shader);
if (ARBShaderObjects.glGetObjectParameteriARB(shader, ARBShaderObjects.GL_OBJECT_COMPILE_STATUS_ARB) == GL11.GL_FALSE)
throw new RuntimeException("Error creating shader: " + getLogInfo(shader));
return shader;
}
catch(Exception exc) {
ARBShaderObjects.glDeleteObjectARB(shader);
throw exc;
}
}
private static String getLogInfo(int obj) {
return ARBShaderObjects.glGetInfoLogARB(obj, ARBShaderObjects.glGetObjectParameteriARB(obj, ARBShaderObjects.GL_OBJECT_INFO_LOG_LENGTH_ARB));
}
private String readFileAsString(String filename) throws Exception {
StringBuilder source = new StringBuilder();
FileInputStream in = new FileInputStream(filename);
Exception exception = null;
BufferedReader reader;
try{
reader = new BufferedReader(new InputStreamReader(in,"UTF-8"));
Exception innerExc= null;
try {
String line;
while((line = reader.readLine()) != null)
source.append(line).append('\n');
}
catch(Exception exc) {
exception = exc;
}
finally {
try {
reader.close();
}
catch(Exception exc) {
if(innerExc == null)
innerExc = exc;
else
exc.printStackTrace();
}
}
if(innerExc != null)
throw innerExc;
}
catch(Exception exc) {
exception = exc;
}
finally {
try {
in.close();
}
catch(Exception exc) {
if(exception == null)
exception = exc;
else
exc.printStackTrace();
}
if(exception != null)
throw exception;
}
return source.toString();
}
}
screen.frag
varying vec4 vertColor;
void main(){
gl_FragColor = vertColor;
}
screen.vert
改变vec4 vertColor;
void main(){
gl_Position = gl_ModelViewProjectionMatrix*gl_Vertex;
vertColor = vec4(0.6, 0.3, 0.4, 1.0);
}