Openg GL 2.0 Android 错误 0x501 (GL_INVALID_VALUE)
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时间：2020-08-20 06:49:04 来源:igfitidea点击:
Openg GL 2.0 Android error 0x501 (GL_INVALID_VALUE)
提问by Billybonks
I am trying to build a little Open GL2.0 demo application on android but i am getting the following errors
我正在尝试在 android 上构建一个小的 Open GL2.0 演示应用程序，但我收到以下错误
in log cat
在日志猫
07-02 20:50:40.110: E/libEGL(1252): call to OpenGL ES API with no current context (logged once per thread)
07-02 20:50:40.110: E/libEGL(1252): call to OpenGL ES API with no current context (logged once per thread)
07-02 20:50:40.110: E/libEGL(1252): call to OpenGL ES API with no current context (logged once per thread)
07-02 20:50:40.110: E/libEGL(1252): call to OpenGL ES API with no current context (logged once per thread)
07-02 20:50:40.110: E/libEGL(1252): call to OpenGL ES API with no current context (logged once per thread)
07-02 20:50:40.110: E/libEGL(1252): call to OpenGL ES API with no current context (logged once per thread)
07-02 20:50:40.110: E/libEGL(1252): call to OpenGL ES API with no current context (logged once per thread)
07-02 20:50:40.110: E/libEGL(1252): call to OpenGL ES API with no current context (logged once per thread)
07-02 20:50:40.110: E/libEGL(1252): call to OpenGL ES API with no current context (logged once per thread)
07-02 20:50:40.110: E/libEGL(1252): call to OpenGL ES API with no current context (logged once per thread)
in the Console
在控制台中
[2012-07-02 20:50:44 - Emulator] development/tools/emulator/opengl/host/libs/Translator/GLES_V2/GLESv2Imp.cpp:glGetAttribLoc ation:826 error 0x501
[2012-07-02 20:50:44 - Emulator] development/tools/emulator/opengl/host/libs/Translator/GLES_V2/GLESv2Imp.cpp:glGetUniformLocation:1383 error 0x501
my code
我的代码
View
看法
package limitliss.graphics.play;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;
import android.content.Context;
import android.opengl.GLES20;
import android.opengl.GLSurfaceView;
import android.opengl.GLSurfaceView.Renderer;
import android.opengl.GLU;
public class OGLView extends GLSurfaceView implements Renderer {
private int mColorType = 0;
private float rotx = 0.0f;
private float roty = 0.0f;
Triangle tri = new Triangle();
public OGLView(Context context) {
super(context);
setEGLContextClientVersion(2);
this.setRenderer(this);
setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
// TODO Auto-generated constructor stub
}
public static int loadShader(int type, String shaderCode){
// create a vertex shader type (GLES20.GL_VERTEX_SHADER)
// or a fragment shader type (GLES20.GL_FRAGMENT_SHADER)
int shader = GLES20.glCreateShader(type);
// add the source code to the shader and compile it
GLES20.glShaderSource(shader, shaderCode);
GLES20.glCompileShader(shader);
return shader;
}
public void onSurfaceCreated(GL10 unused, EGLConfig config) {
// Set the background frame color
GLES20.glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
tri.draw();
}
public void onDrawFrame(GL10 unused) {
// Redraw background color
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
tri.draw();
}
public void onSurfaceChanged(GL10 unused, int width, int height) {
GLES20.glViewport(0, 0, width, height);
}
}
Triangle
package limitliss.graphics.play;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import javax.microedition.khronos.opengles.GL10;
import android.opengl.GLES20;
public class Triangle {
float color[] = { 0.63671875f, 0.76953125f, 0.22265625f, 1.0f };
private FloatBuffer vertexBuffer;
int mProgram;
int mPositionHandle;
private final String vertexShaderCode =
"attribute vec4 vPosition;" +
"void main() {" +
" gl_Position = vPosition;" +
"}";
private final String fragmentShaderCode =
"precision mediump float;" +
"uniform vec4 vColor;" +
"void main() {" +
" gl_FragColor = vColor;" +
"}";
// number of coordinates per vertex in this array
static final int COORDS_PER_VERTEX = 3;
static float triangleCoords[] = { // in counterclockwise order:
0.0f, 0.622008459f, 0.0f, // top
-0.5f, -0.311004243f, 0.0f, // bottom left
0.5f, -0.311004243f, 0.0f}; // bottom right
public Triangle() {
// initialize vertex byte buffer for shape coordinates
ByteBuffer bb = ByteBuffer.allocateDirect(
// (number of coordinate values * 4 bytes per float)
triangleCoords.length * 4);
// use the device hardware's native byte order
bb.order(ByteOrder.nativeOrder());
// create a floating point buffer from the ByteBuffer
vertexBuffer = bb.asFloatBuffer();
// add the coordinates to the FloatBuffer
vertexBuffer.put(triangleCoords);
// set the buffer to read the first coordinate
vertexBuffer.position(0);
int vertexShader = OGLView.loadShader(GLES20.GL_VERTEX_SHADER, vertexShaderCode);
int fragmentShader = OGLView.loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentShaderCode);
mProgram = GLES20.glCreateProgram(); // create empty OpenGL ES Program
GLES20.glAttachShader(mProgram, vertexShader); // add the vertex shader to program
GLES20.glAttachShader(mProgram, fragmentShader); // add the fragment shader to program
GLES20.glLinkProgram(mProgram);
}
public void draw() {
// Add program to OpenGL ES environment
GLES20.glUseProgram(mProgram);
// get handle to vertex shader's vPosition member
mPositionHandle = GLES20.glGetAttribLocation(mProgram, "vPosition");
// Enable a handle to the triangle vertices
GLES20.glEnableVertexAttribArray(mPositionHandle);
// Prepare the triangle coordinate data
GLES20.glVertexAttribPointer(mPositionHandle, COORDS_PER_VERTEX,
GLES20.GL_FLOAT, false,
COORDS_PER_VERTEX, vertexBuffer);
// get handle to fragment shader's vColor member
int mColorHandle = GLES20.glGetUniformLocation(mProgram, "vColor");
// Set color for drawing the triangle
GLES20.glUniform4fv(mColorHandle, 1, color, 0);
// Draw the triangle
GLES20.glDrawArrays(GLES20.GL_TRIANGLES, 0, 3);
// Disable vertex array
GLES20.glDisableVertexAttribArray(mPositionHandle);
}
public void render(GL10 gl){
gl.glPushMatrix();
gl.glColor4f(this.color[0],this.color[1],this.color[2],this.color[3]);
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDrawArrays(GL10.GL_TRIANGLE_FAN, 0, 3);
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glPopMatrix();
}
}
回答by Tim
You're getting call to OpenGL ES API with no current contexterrors because you're creating your triangle Triangle tri = new Triangle();outside of the OpenGL thread (and the triangle constructor is making opengl calls). Only the code inside the OpenGL callbacks (onSurfaceCreated, onDrawFrame, etc) are executed on the opengl thread.
您收到call to OpenGL ES API with no current context错误是因为您在Triangle tri = new Triangle();OpenGL 线程之外创建了三角形 （并且三角形构造函数正在调用 opengl）。只有 OpenGL 回调中的代码（onSurfaceCreated、onDrawFrame 等）在 opengl 线程上执行。
Put tri = new Triangle()inside of onSurfaceCreatedand those errors should go away.
放在tri = new Triangle()里面，onSurfaceCreated这些错误应该消失。
