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ColdDoT

OpenGL C++ DDS to PNG

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Hello all, There is a game called WonderKing, and they store all there pictures in headerless DDS files. Well i've been able to track down the patterns of the file name with what type of DDS format they are. And the same for the filesize and width height. Currently they i got 4 formats figured out: DXT1 DXT5 A4R4G4B4 A1R5G5B5 There are 4 textures of 4096kb whom i can not figure out what type they are. Anyways i'm currently converthing them to png through opengl. i first use
	glGenTextures(1, &textureNo);
	glBindTexture(GL_TEXTURE_2D, textureNo);

	switch(format.name)
	{
		case DXT1:
		case DXT5:
			glCompressedTexImage2D(GL_TEXTURE_2D, 0, format.dataType, width, height, 0, fileSize*1024, rawBuffer);
		break;
		case A4R4G4B4:
		case A1R5G5B5:
			glTexImage2D(GL_TEXTURE_2D, 0, format.internalFormat, width, height, 0, format.pixelFormat, format.dataType, rawBuffer);
		break;
	}

	rgbBuffer = (GLubyte*)malloc(width*height*4);
	glGetTexImage(GL_TEXTURE_2D, 0, GL_RGBA, GL_UNSIGNED_BYTE, rgbBuffer);
The glTexImage2D and glCompressedTexImage2D are for preps and then calling glGetTexImage to get the the image information in the correct format. I'm not sure if this is faster then skipping opengl and just setting the pixel buffer correct by plain C (if so is there some documentation on buffers with formats etc) After that i use lodepng to encode the picture to png and save it. However this step takes like 10-20 secs per texture. So my question is, how would you tackle this problem? If you wanna convert dds files to png, and preverable also show the pictures is a GUI (currently i'm using a opengl rendering area to render the textures to) This is my first, post btw so thanks for reading and taking your time. +ColdDoT

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