0
我目前正在尝试渲染Opengl中的纹理对象。一切工作正常,直到我想渲染具有透明度的纹理。而不是显示对象透明,它只是呈现全黑色。DDS纹理透明呈现黑色Opengl
FO加载纹理文件的方法是这样的:
// structures for reading and information variables
char magic[4];
unsigned char header[124];
unsigned int width, height, linearSize, mipMapCount, fourCC;
unsigned char* dataBuffer;
unsigned int bufferSize;
fstream file(path, ios::in|ios::binary);
// read magic and header
if (!file.read((char*)magic, sizeof(magic))){
cerr<< "File " << path << " not found!"<<endl;
return false;
}
if (magic[0]!='D' || magic[1]!='D' || magic[2]!='S' || magic[3]!=' '){
cerr<< "File does not comply with dds file format!"<<endl;
return false;
}
if (!file.read((char*)header, sizeof(header))){
cerr<< "Not able to read file information!"<<endl;
return false;
}
// derive information from header
height = *(int*)&(header[8]);
width = *(int*)&(header[12]);
linearSize = *(int*)&(header[16]);
mipMapCount = *(int*)&(header[24]);
fourCC = *(int*)&(header[80]);
// determine dataBuffer size
bufferSize = mipMapCount > 1 ? linearSize * 2 : linearSize;
dataBuffer = new unsigned char [bufferSize*2];
// read data and close file
if (file.read((char*)dataBuffer, bufferSize/1.5))
cout<<"Loading texture "<<path<<" successful"<<endl;
else{
cerr<<"Data of file "<<path<<" corrupted"<<endl;
return false;
}
file.close();
// check pixel format
unsigned int format;
switch(fourCC){
case FOURCC_DXT1:
format = GL_COMPRESSED_RGBA_S3TC_DXT1_EXT;
break;
case FOURCC_DXT3:
format = GL_COMPRESSED_RGBA_S3TC_DXT3_EXT;
break;
case FOURCC_DXT5:
format = GL_COMPRESSED_RGBA_S3TC_DXT5_EXT;
break;
default:
cerr << "Compression type not supported or corrupted!" << endl;
return false;
}
glGenTextures(1, &ID);
glBindTexture(GL_TEXTURE_2D, ID);
glPixelStorei(GL_UNPACK_ALIGNMENT,1);
unsigned int blockSize = (format == GL_COMPRESSED_RGBA_S3TC_DXT1_EXT) ? 8 : 16;
unsigned int offset = 0;
/* load the mipmaps */
for (unsigned int level = 0; level < mipMapCount && (width || height); ++level) {
unsigned int size = ((width+3)/4)*((height+3)/4)*blockSize;
glCompressedTexImage2D(GL_TEXTURE_2D, level, format, width, height,
0, size, dataBuffer + offset);
offset += size;
width /= 2;
height /= 2;
}
textureType = DDS_TEXTURE;
return true;
在我只设置gl_FragColor =的Texture2D片段着色器(myTextureSampler,UVcoords)
我希望有一个简单的解释,例如因为缺少一些代码。 在openGL初始化中我glEnabled GL_Blend并设置了一个混合函数。
有没有人有我做错了什么的想法?
感谢您的建议。不幸的是,包括这些变化并没有什么区别。在我看来,加载dds或着色器时可能会出现问题。如果我为gl_FragColor设置了一个固定的alpha值,透明效果。只有从纹理上加载某些东西时才会出错。 OMG! – 2013-02-25 22:05:02
OMG!我解决了它。如此愚蠢。起初,我只为图纸的一部分启用了GL_BLEND,而不是那些需要透明的部分。然后这是正确的,但加载了错误的纹理。对不起,打扰你。并再次感谢您的帮助。我已经放弃了这一点。 :d – 2013-02-25 22:26:02