我正在尝试通过将Open GL ES纹理设置为Android surfaceTexture来捕获视频并将其显示到屏幕上。由于我正在使用Google Cardboard，因此无法像这个教程中所述那样使用TextureView并实现SurfaceTextureListener。
我已经按照Android文档中关于如何初始化Open GL ES 2.0并使用它的说明，以及这个教程上的纹理贴图说明进行了操作。
将两者结合起来，我得到一个空白屏幕，并偶尔在控制台窗口中得到<core_glBindTexture:572>: GL_INVALID_OPERATION。由于对许多我不知道的新概念感到不知所措，因此我无法调试或理解这两种方法是否可以像这样使用。这是我的绘图代码，它是在MainActivity类的onSurfaceCreated()中初始化的，并从Cardboard的绘图函数onEyeDraw()中绘制。
package com.example.rich.test3;
import android.hardware.Camera;
import android.opengl.GLES20;
import android.view.TextureView;
import java.nio.ShortBuffer;
import java.nio.FloatBuffer;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
/**
* Created by rich on 03/05/2015.
*/
public class Square {
private java.nio.FloatBuffer vertexBuffer;
private java.nio.ShortBuffer drawListBuffer;
private final java.nio.FloatBuffer mCubeTextureCoordinates;
float color[] = { 1.f, 1.f, 1.f, 1.0f };
private final String vertexShaderCode =
"attribute vec4 vPosition;" +
"attribute vec2 a_TexCoordinate;" +
"varying vec2 v_TexCoordinate;" +
"void main() {" +
" gl_Position = vPosition;" +
" v_TexCoordinate = a_TexCoordinate;" +
"}";
private final String fragmentShaderCode =
"precision mediump float;" +
"uniform vec4 vColor;" +
"uniform sampler2D u_Texture;" +
"varying vec2 v_TexCoordinate;" +
"void main() {" +
"gl_FragColor = (texture2D(u_Texture, v_TexCoordinate));" +
"}";
// number of coordinates per vertex in this array
static final int COORDS_PER_VERTEX = 3;
static float squareCoords[] = {
-0.5f, -0.5f, 0.0f, // bottom left
0.5f, -0.5f, 0.0f, // bottom right
-0.5f, 0.5f, 0.0f, // top left
0.5f, 0.5f, 0.0f}; // top right
private short drawOrder[] = { 0, 1, 2, 0, 2, 3 }; // order to draw vertices
private int mProgram;
private int mPositionHandle;
private int mColorHandle;
private int mTextureUniformHandle;
private int mTextureCoordinateHandle;
private final int mTextureCoordinateDataSize = 2;
private final int vertexCount = squareCoords.length / COORDS_PER_VERTEX;
private final int vertexStride = COORDS_PER_VERTEX * 4; // 4 bytes per vertex
private int mTextureDataHandle;
float textureCoordinates[] =
{0.0f, 1.0f,
1.0f, 1.0f,
0.0f, 0.0f,
1.0f, 0.0f };
Camera _camera;
TextureView _textureView;
int[] textures;
android.graphics.SurfaceTexture _surface;
public Square()
{
ByteBuffer bb = ByteBuffer.allocateDirect(
// (# of coordinate values * 4 bytes per float)
squareCoords.length * 4);
bb.order(ByteOrder.nativeOrder());
vertexBuffer = bb.asFloatBuffer();
vertexBuffer.put(squareCoords);
vertexBuffer.position(0);
// initialize byte buffer for the draw list
ByteBuffer dlb = ByteBuffer.allocateDirect(
// (# of coordinate values * 2 bytes per short)
drawOrder.length * 2);
dlb.order(ByteOrder.nativeOrder());
drawListBuffer = dlb.asShortBuffer();
drawListBuffer.put(drawOrder);
drawListBuffer.position(0);
mCubeTextureCoordinates = ByteBuffer.allocateDirect(textureCoordinates.length * 4)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
mCubeTextureCoordinates.put(textureCoordinates).position(0);
// create empty OpenGL ES Program
mProgram = GLES20.glCreateProgram();
textures = new int[1];
GLES20.glGenTextures(1, textures, 0);
_surface = new android.graphics.SurfaceTexture(textures[0]);
_camera = Camera.open();
Camera.Size previewSize = _camera.getParameters().getPreviewSize();
try
{
_camera.setPreviewTexture(_surface);
}
catch (java.io.IOException ex)
{
// Console.writeLine (ex.Message);
}
final int vertexShaderHandle = GLES20.glCreateShader(GLES20.GL_VERTEX_SHADER);
GLES20.glShaderSource(vertexShaderHandle, vertexShaderCode);
GLES20.glCompileShader(vertexShaderHandle);
final int[] compileStatus = new int[1];
GLES20.glGetShaderiv(vertexShaderHandle, GLES20.GL_COMPILE_STATUS, compileStatus, 0);
if (compileStatus[0] == 0)
{
//do check here
}
final int fragmentShaderHandle = GLES20.glCreateShader(GLES20.GL_FRAGMENT_SHADER);
GLES20.glShaderSource(fragmentShaderHandle, fragmentShaderCode);
GLES20.glCompileShader(fragmentShaderHandle);
GLES20.glGetShaderiv(fragmentShaderHandle, GLES20.GL_COMPILE_STATUS, compileStatus, 0);
if (compileStatus[0] == 0)
{
//do check here
}
GLES20.glAttachShader(mProgram, vertexShaderHandle);
GLES20.glAttachShader(mProgram, fragmentShaderHandle);
GLES20.glBindAttribLocation(mProgram, 0, "a_Position");
GLES20.glBindAttribLocation(mProgram, 0, "a_TexCoordinate");
GLES20.glLinkProgram(mProgram);
final int[] linkStatus = new int[1];
GLES20.glGetProgramiv(mProgram, GLES20.GL_LINK_STATUS, linkStatus, 0);
if (linkStatus[0] == 0)
{
//do check here
}
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textures[0]);
mTextureDataHandle = textures[0];
// Set filtering
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_NEAREST);
}
public void draw()
{
_surface.updateTexImage();
GLES20.glUseProgram(mProgram);
mTextureUniformHandle = GLES20.glGetUniformLocation(mProgram, "u_Texture");
mPositionHandle = GLES20.glGetAttribLocation(mProgram, "a_Position");
mColorHandle = GLES20.glGetAttribLocation(mProgram, "a_Color");
mTextureCoordinateHandle = GLES20.glGetAttribLocation(mProgram, "a_TexCoordinate");
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mTextureDataHandle);
GLES20.glVertexAttribPointer(mPositionHandle, COORDS_PER_VERTEX,
GLES20.GL_FLOAT, false,
vertexStride, vertexBuffer);
GLES20.glVertexAttribPointer(mTextureCoordinateHandle, mTextureCoordinateDataSize, GLES20.GL_FLOAT, false,
0, mCubeTextureCoordinates);
GLES20.glEnableVertexAttribArray(mTextureCoordinateHandle);
GLES20.glEnableVertexAttribArray(mPositionHandle);
GLES20.glUniform1i(mTextureUniformHandle, 0);
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, vertexCount);
GLES20.glDisableVertexAttribArray(mPositionHandle);
}
}