OpenGL ES在android上调用glCreateShader()时崩溃

Question

我基本上遵循了android文档的指南，除了几个变量名，我在一个片段中渲染。我已经花了一点时间注释掉行，我设法弄清楚

public static int loadShader(int type, String shaderCode) {
int shader = GLES20.glCreateShader(type);
//System.out.println(shader + " ass");
//GLES20.glShaderSource(shader, shaderCode);
//GLES20.glCompileShader(shader);
//return shader;
return 0;
}

glCreateShader方法使应用程序崩溃。它不返回任何东西，它只是崩溃。类型输入总是GLES20.GL_VERTEX_SHADER或GLES20.GL_FRAGMENT_SHADER，两者都会崩溃。

渲染器类的其余部分看起来像这样

public class OpenGLRenderer implements GLSurfaceView.Renderer {
private Triangle trangle;
@Override
public void onSurfaceCreated(GL10 gl10, EGLConfig eglConfig) {
GLES20.glClearColor(0.0f, 1.0f, 0.0f, 1.0f);
trangle = new Triangle();
}
@Override
public void onSurfaceChanged(GL10 gl10, int i, int i1) {
}
@Override
public void onDrawFrame(GL10 gl10) {
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
//trangle.draw();
}

public static int loadShader(int type, String shaderCode) {
int shader = GLES20.glCreateShader(type);
//System.out.println(shader + " ass");
//GLES20.glShaderSource(shader, shaderCode);
//GLES20.glCompileShader(shader);
//return shader;
return 0;
}

这是我的三角形类:

public class Triangle {
private FloatBuffer vertexBuffer;
private final int shaderProgram;
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;" +
"}";
static float[] triangleCoords = {
0.0f, 0.5f, 0.0f,
-0.5f,-0.3f, 0.0f,
0.5f, -0.3f, 0.0f
};
static final int coordsInVertex = 3, vertexCount = triangleCoords.length / coordsInVertex, vertexStride = coordsInVertex * 4;
private int positionHandle, colorHandle;
float color[] = {1f, 0f, 0f, 1f};
public Triangle () {
ByteBuffer byteBuffer = ByteBuffer.allocateDirect(triangleCoords.length*4);
byteBuffer.order(ByteOrder.nativeOrder());
vertexBuffer = byteBuffer.asFloatBuffer();
vertexBuffer.put (triangleCoords);
vertexBuffer.position(0);
int vertexShader = OpenGLRenderer.loadShader(GLES20.GL_VERTEX_SHADER, vertexShaderCode);
int fragmentShader = OpenGLRenderer.loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentShaderCode);
shaderProgram = GLES20.glCreateProgram();
GLES20.glAttachShader(shaderProgram, vertexShader);
GLES20.glAttachShader(shaderProgram, fragmentShader);
GLES20.glLinkProgram(shaderProgram);
}
public void draw () {
GLES20.glUseProgram(shaderProgram);
positionHandle = GLES20.glGetAttribLocation(shaderProgram, "vPosition");
GLES20.glEnableVertexAttribArray(positionHandle);
GLES20.glVertexAttribPointer(positionHandle, coordsInVertex, GLES20.GL_FLOAT, false, vertexStride, vertexBuffer);
colorHandle = GLES20.glGetUniformLocation(shaderProgram, "vColor");
GLES20.glUniform4fv(colorHandle, 1, color, 0);
GLES20.glDrawArrays(GLES20.GL_TRIANGLES, 0, vertexCount);
GLES20.glDisableVertexAttribArray(positionHandle);
}
}

有人能给点光吗?

Answer 1

没有发现您提供的上述源代码中的任何问题或错误，并且在与GLSurfaceView连接时完全可行。

我认为问题是在配置GLSurfaceView其中必须显式地设置EGLContextClientVersionsetRenderer之前的OpenGL-ES上下文;没有eglContext程序将不会执行任何GL操作。

GLSurfaceView view = findViewById(R.id.glview);
view.setEGLContextClientVersion(2);
view.setRenderer(new OpenGLRenderer());