原文：http://blog.csdn.net/u011270282/article/details/51505755
在gpuimagerender里面有如下方法，GPUImage.ScaleType.CENTER_CROP表示剪裁，可以修改他的参数达到自己的需要。
private void adjustImageScaling() {
float outputWidth = mOutputWidth;
float outputHeight = mOutputHeight;
if (mRotation == Rotation.ROTATION_270 || mRotation == Rotation.ROTATION_90) {
outputWidth = mOutputHeight;
outputHeight = mOutputWidth;
}
float ratio1 = outputWidth / mImageWidth;
float ratio2 = outputHeight / mImageHeight;
float ratioMax = Math.max(ratio1, ratio2);
int imageWidthNew = Math.round(mImageWidth * ratioMax);
int imageHeightNew = Math.round(mImageHeight * ratioMax);
float ratioWidth = imageWidthNew / outputWidth;
float ratioHeight = imageHeightNew / outputHeight;
float[] cube = CUBE;
float[] textureCords = TextureRotationUtil.getRotation(mRotation, mFlipHorizontal, mFlipVertical);
if (mScaleType == GPUImage.ScaleType.CENTER_CROP) {
float distHorizontal = (1 - 1 / ratioWidth) / 2;
float distVertical = (1 - 1 / ratioHeight) / 2;
textureCords = new float[]{
addDistance(textureCords[0], distHorizontal), addDistance(textureCords[1], distVertical),
addDistance(textureCords[2], distHorizontal), addDistance(textureCords[3], distVertical),
addDistance(textureCords[4], distHorizontal), addDistance(textureCords[5], distVertical),
addDistance(textureCords[6], distHorizontal), addDistance(textureCords[7], distVertical),
};
} else {
cube = new float[]{
CUBE[0] / ratioHeight, CUBE[1] / ratioWidth,
CUBE[2] / ratioHeight, CUBE[3] / ratioWidth,
CUBE[4] / ratioHeight, CUBE[5] / ratioWidth,
CUBE[6] / ratioHeight, CUBE[7] / ratioWidth,
};
}
mGLCubeBuffer.clear();
mGLCubeBuffer.put(cube).position(0);
mGLTextureBuffer.clear();
mGLTextureBuffer.put(textureCords).position(0);
}
