How to calculate the size of an image in the graphicscard ram?
Basically the data is uncompressed in memory, so its size is with*height*depth. This is independent of the fact whether the image has been read from a compressed file on disc (like a jpg or png image). The bit depth plays an important role – a color rgba image is four times as expensive as greyscale or indexed. You can set the bit depth with the Format pin in the FileTexture (EX9.Texture) node (the resulting bit depth is the sum of all the numbers in the format) In practice the memory consumption is driver dependent in many ways. Some drivers allocate more memory to round height/width to the next power of 2; the driver might create additional copies for better reading; mipmaps will add to this etc. So the Memory (Debug EX9) node will give authorative answers, and it makes sense to create automated tests and do some scientific reasoning (and post the results here).
