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編輯代碼加入，請參見下面正確的頂點着色器代碼？ OpenGL ES 2.0的
編輯2個 - 截圖來自包括在底部裝置與解釋和說明
編輯3 - 新的代碼添加
我有2個課程，一個渲染和一個自定義'四'級。
我的這些聲明在一流水平在我的渲染器類：
final float[] mMVPMatrix = new float[16];
final float[] mProjMatrix = new float[16];
final float[] mVMatrix = new float[16];
在我onSurfaceChanged方法我有：
@覆蓋 公共無效onSurfaceChanged（GL10 GL，詮釋寬度，高度INT ）{
GLES20.glViewport(0, 0, width, height);
float ratio = (float) width/height;
Matrix.frustumM(mProjMatrix, 0, -ratio, ratio, -1, 1, 3, 7);
}
和....
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
// TODO Auto-generated method stub
myBitmap = BitmapFactory.decodeResource(curView.getResources(), R.drawable.box);
//Create new Dot objects
dot1 = new Quad();
dot1.setTexture(curView, myBitmap);
dot1.setSize(300,187); //These numbers are the size but are redundant/not used at the moment.
myBitmap.recycle();
//Set colour to black
GLES20.glClearColor(0, 0, 0, 1);
}
最後，來自這個班，onDrawFrame：
@Override
public void onDrawFrame(GL10 gl) {
// TODO Auto-generated method stub
//Paint the screen the colour defined in onSurfaceCreated
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
// Set the camera position (View matrix) so looking from the front
Matrix.setLookAtM(mVMatrix, 0, 0, 0, 3, 0f, 0f, 0f, 0f, 1.0f, 0.0f);
// Combine
Matrix.multiplyMM(mMVPMatrix, 0, mProjMatrix, 0, mVMatrix, 0);
dot1.rotateQuad(0,0,45, mMVPMatrix); //x,y,angle and matrix passed in
}
然後，在我的四等級：
該聲明在類級別：
private float[] mRotationMatrix = new float[16];
private final float[] mMVPMatrix = new float[16];
private final float[] mProjMatrix = new float[16];
private final float[] mVMatrix = new float[16];
private int mMVPMatrixHandle;
private int mPositionHandle;
private int mRotationHandle;
//Create our vertex shader
String strVShader =
"uniform mat4 uMVPMatrix;" +
"uniform mat4 uRotate;" +
"attribute vec4 a_position;\n"+
"attribute vec2 a_texCoords;" +
"varying vec2 v_texCoords;" +
"void main()\n" +
"{\n" +
// "gl_Position = a_position * uRotate;\n"+
// "gl_Position = uRotate * a_position;\n"+
"gl_Position = a_position * uMVPMatrix;\n"+
// "gl_Position = uMVPMatrix * a_position;\n"+
"v_texCoords = a_texCoords;" +
"}";
//Fragment shader
String strFShader =
"precision mediump float;" +
"varying vec2 v_texCoords;" +
"uniform sampler2D u_baseMap;" +
"void main()" +
"{" +
"gl_FragColor = texture2D(u_baseMap, v_texCoords);" +
"}";
然後設置紋理的方法（唐不過認爲這與這個問題有關!!）
public void setTexture(GLSurfaceView view, Bitmap imgTexture){
this.imgTexture=imgTexture;
iProgId = Utils.LoadProgram(strVShader, strFShader);
iBaseMap = GLES20.glGetUniformLocation(iProgId, "u_baseMap");
iPosition = GLES20.glGetAttribLocation(iProgId, "a_position");
iTexCoords = GLES20.glGetAttribLocation(iProgId, "a_texCoords");
texID = Utils.LoadTexture(view, imgTexture);
}
最後，我的'rotateQuad'方法（目前應該繪製並旋轉四邊形）。
public void rotateQuad(float x, float y, int angle, float[] mvpMatrix){
Matrix.setRotateM(mRotationMatrix, 0, angle, 0, 0, 0.1f);
// Matrix.translateM(mRotationMatrix, 0, 0, 0, 0); //Removed temporarily
// Combine the rotation matrix with the projection and camera view
Matrix.multiplyMM(mvpMatrix, 0, mRotationMatrix, 0, mvpMatrix, 0);
float[] vertices = {
-.5f,.5f,0, 0,0,
.5f,.5f,0, 1,0,
-.5f,-.5f,0, 0,1,
.5f,-.5f,0, 1,1
};
vertexBuf = ByteBuffer.allocateDirect(vertices.length * 4).order(ByteOrder.nativeOrder()).asFloatBuffer();
vertexBuf.put(vertices).position(0);
//Bind the correct texture
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, texID);
//Use program
GLES20.glUseProgram(iProgId);
// get handle to shape's transformation matrix
mMVPMatrixHandle = GLES20.glGetUniformLocation(iProgId, "uMVPMatrix");
// Apply the projection and view transformation
GLES20.glUniformMatrix4fv(mMVPMatrixHandle, 1, false, mvpMatrix, 0);
// get handle to shape's rotation matrix
mRotationHandle = GLES20.glGetUniformLocation(iProgId, "uRotate");
// Apply the projection and view transformation
GLES20.glUniformMatrix4fv(mRotationHandle, 1, false, mRotationMatrix, 0);
//Set starting position for vertices
vertexBuf.position(0);
//Specify attributes for vertex
GLES20.glVertexAttribPointer(iPosition, 3, GLES20.GL_FLOAT, false, 5 * 4, vertexBuf);
//Enable attribute for position
GLES20.glEnableVertexAttribArray(iPosition);
//Set starting position for texture
vertexBuf.position(3);
//Specify attributes for vertex
GLES20.glVertexAttribPointer(iTexCoords, 2, GLES20.GL_FLOAT, false, 5 * 4, vertexBuf);
//Enable attribute for texture
GLES20.glEnableVertexAttribArray(iTexCoords);
//Draw it
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
}
編輯2.
這是我四是在屏幕的中心繪製。沒有旋轉。
這是相同的四在45度與代碼旋轉 「GL_POSITION = a_position * uMVPMatrix;」 +在我的頂點着色器（它現在來自不同的項目，所以着色器變量是a_position而不是vPosition），它看起來是正確的！
但是，這是相同的四在+45度的2個着色器變量旋轉切換（所以他們讀「GL_POSITION = uMVPMatrix * a_position;」 - 你可以看到，這是不完全正確。
還只是一個側面說明，你不能在這裏看到它作爲quare是對稱的，但每種方法也沿相反方向等....
的y幫助表示讚賞。
嗨@SebbyJohanns，我又已經編輯我更多的碼Q -is這還不夠的時候是發生在訴說？謝謝。 – Zippy 2013-04-05 15:52:08
需要頂點shader代碼也是如此 – 2013-04-05 16:04:06
如有需要，請多加謝謝 – Zippy 2013-04-05 16:08:50