android opengl渲染不正确

Question

渲染纹理到视口时出现问题。 正在渲染屏幕，但纹理（256 * 256）与我上传的原始jpg图片不一样。

请查找附加的图像和渲染代码。一个图像是原始jpg，另一个图像是android手机上渲染的纹理。

original

rendered image

这是我的MainActivity代码：

private void initialize() { 
    if (hasGLES20()) { 
     GLSurfaceView mGLView = new GLSurfaceView(this); 
     mGLView.setEGLContextClientVersion(2); 
     mGLView.setPreserveEGLContextOnPause(true); 
     mGLView.setEGLConfigChooser(8, 8, 8, 8, 16, 0); 
     mGLView.setEGLConfigChooser(true); 
     mGLView.setRenderer(this); 
     setContentView(mGLView); 
    } 
} 

@Override 
public void onSurfaceCreated(GL10 gl10, EGLConfig eglConfig) { 
    GLES20.glClearColor(0.5f,0.3f,0.8f,1.0f); 


    String vertexShaderSource = "" + 
    "uniform mat4 u_projection;" + 
    "uniform mat4 u_model;" + 
    "uniform mat4 u_view;" + 
    "" + 
    "attribute vec4 a_position;" + 
    "attribute vec2 a_texCoord;" + 
    "" + 
    "varying vec2 v_texCoord;" + 

    "" + 
    "void main()" + 
    "{" + 
    " gl_Position = u_projection * u_view * u_model * a_position;" + 

    " v_texCoord = a_texCoord;" + 

    "}"; 

    String fragmentShaderSource = "" + 

    "varying vec2 v_texCoord;" + 
    "uniform sampler2D s_texture;" + 
    "" + 
    "void main() {" + 
    " vec4 texCol = texture2D(s_texture, v_texCoord);" + 
    " gl_FragColor = texCol;" + 

    "}"; 

    texture = new Texture(this); 


    vertexShader = GLES20.glCreateShader(GLES20.GL_VERTEX_SHADER); 
    GLES20.glShaderSource(vertexShader, vertexShaderSource); 
    GLES20.glCompileShader(vertexShader); 
    String vertexShaderCompileLog = GLES20.glGetShaderInfoLog(vertexShader); 

    fragmentShader = GLES20.glCreateShader(GLES20.GL_FRAGMENT_SHADER); 
    GLES20.glShaderSource(fragmentShader, fragmentShaderSource); 
    GLES20.glCompileShader(fragmentShader); 
    String fragmentShaderCompileLog = GLES20.glGetShaderInfoLog(fragmentShader); 

    programID = GLES20.glCreateProgram(); 
    GLES20.glAttachShader(programID,vertexShader); 
    GLES20.glAttachShader(programID,fragmentShader); 
    GLES20.glBindAttribLocation(programID, 0, "a_position"); 
    GLES20.glBindAttribLocation(programID, 1, "a_texCoord"); 
    GLES20.glLinkProgram(programID); 

    String programLinkLog = GLES20.glGetProgramInfoLog(programID); 
    GLES20.glUseProgram(programID); 

    float[] modelMatrix = new float[16], viewMatrix = new float[16], projectionMatrix = new float[16]; 


    ByteBuffer modelMatrixByteBuffer = ByteBuffer.allocateDirect(modelMatrix.length * 4); 
    modelMatrixByteBuffer.order(ByteOrder.nativeOrder()); 
    FloatBuffer modelMatrixBuffer = modelMatrixByteBuffer.asFloatBuffer(); 
    Matrix.setIdentityM(modelMatrix,0); 
    Matrix.translateM(modelMatrix, 0, modelMatrix,0,0,0,-2.0f); 
    modelMatrixBuffer.put(modelMatrix); 
    modelMatrixBuffer.rewind(); 

    // translate model to 0,0,-2 
    Matrix.setLookAtM(viewMatrix,0,0,0,0,0,0,-10,0,1,0); 
    Matrix.perspectiveM(projectionMatrix,0,70,256/256,0.1f,100); 

    GLES20.glUniformMatrix4fv(GLES20.glGetUniformLocation(programID,"u_projection"),1,false,projectionMatrix,0); 
    GLES20.glUniformMatrix4fv(GLES20.glGetUniformLocation(programID,"u_view"),1,false,viewMatrix,0);   
    GLES20.glUniformMatrix4fv(GLES20.glGetUniformLocation(programID,"u_model"),1,false,modelMatrixBuffer); 

} 

@Override 
public void onSurfaceChanged(GL10 gl10, int width, int height) { 
    GLES20.glViewport(0,0,256,256); 
} 

@Override 
public void onDrawFrame(GL10 gl10){ 

     GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT); 
     float vertices[] = 
     { 
      -1.0f, 1.0f, 0.0f, 
      -1.0f, -1.0f, 0.0f, 
      1.0f, 1.0f, 0.0f, 
      1.0f, -1.0f, 0.0f 
     }; 

     float textureCoord[] = 
     { 
      0.0f, 1.0f, 
      0.0f, 0.0f, 
      1.0f, 1.0f, 
      0.0f, 1.0f 
     }; 


     ByteBuffer verticesByteBuffer = ByteBuffer.allocateDirect(vertices.length * 4); 
     verticesByteBuffer.order(ByteOrder.nativeOrder()); 
     FloatBuffer verticesBuffer = verticesByteBuffer.asFloatBuffer(); 
     verticesBuffer.put(vertices); 
     verticesBuffer.rewind(); 

     ByteBuffer textureCoordByteBuffer = ByteBuffer.allocateDirect(textureCoord.length * 4); 
     textureCoordByteBuffer.order(ByteOrder.nativeOrder()); 
     FloatBuffer textureCoordBuffer = textureCoordByteBuffer.asFloatBuffer(); 
     textureCoordBuffer.put(textureCoord); 
     textureCoordBuffer.rewind(); 

     GLES20.glVertexAttribPointer(0, 3, GLES20.GL_FLOAT, false, 3 * 4, verticesBuffer); 
     GLES20.glVertexAttribPointer(1, 2, GLES20.GL_FLOAT, false, 2 * 4, textureCoordBuffer); 
     GLES20.glEnableVertexAttribArray(0); 
     GLES20.glEnableVertexAttribArray(1); 



    texture.setTexture(); 
    GLES20.glUniform1i(GLES20.glGetUniformLocation(programID,"s_texture"),0); 
    GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4); 
} 

这是我的负荷质感一流

public class Texture 
{ 
private int m_iTextureId; 

public Texture(Context ctx) 
{ 
    m_iTextureId = loadTexture(ctx, R.drawable.index); 
} 

public void setTexture() 
{ 
    GLES20.glActiveTexture(GLES20.GL_TEXTURE0); 
    GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, m_iTextureId); 
} 

public int loadTexture(Context ctx, int rsrcId) 
{ 
    int[] iTextureId = new int[1]; 
    GLES20.glActiveTexture(GLES20.GL_TEXTURE0); 
    GLES20.glGenTextures(1, iTextureId, 0); 

    if(iTextureId[0] != 0) 
    { 
    GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, iTextureId[0]); 

    BitmapFactory.Options options = new BitmapFactory.Options(); 
    options.inScaled = false; 

    Bitmap bitmap = BitmapFactory.decodeResource(ctx.getResources(), rsrcId, 
               options); 

    GLUtils.texImage2D(GLES20.GL_TEXTURE_2D, 0, bitmap, 0); 
    bitmap.recycle(); 

    GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, 
         GLES20.GL_TEXTURE_MIN_FILTER, 
         GLES20.GL_LINEAR); 

    GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, 
          GLES20.GL_TEXTURE_MAG_FILTER, 
          GLES20.GL_LINEAR); 

    GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, 
      GLES20.GL_TEXTURE_WRAP_S, 
      GLES20.GL_CLAMP_TO_EDGE); 

     GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, 
       GLES20.GL_TEXTURE_WRAP_T, 
       GLES20.GL_CLAMP_TO_EDGE); 
    } 
    else 
    { 
    throw new RuntimeException("Error loading texture"); 
    } 

    return iTextureId[0]; 
    } 

任何帮助吗？

Answer 1

您的纹理坐标是错误的。它们包含相同的坐标两次：

float textureCoord[] = 
{ 
    0.0f, 1.0f, <-- 
    0.0f, 0.0f, 
    1.0f, 1.0f, 
    0.0f, 1.0f <-- 
}; 

为了解决这个替换的最后一个坐标[1,0]而不是[0,1]。