   MipMapping and Speed
  Hi, i have a DirectX 9 application in which you zoom into a texture fast. The problem is that sometimes jitter happens. If i turn off mipmapping the jitter vanishes. Can it be that the switching between the different mipmap-levels is more time-consuming than using just one big texture?Jens   
  Jitter isn't a particularly helpful descriptor here as it could refer to any number of different effects. Does the image 'pop' slightly from one MIP level to the next? If it does, you're probably not using trilinear filtering; enabling it should probably make the effect disappear. If there's a jerkiness (as in the zooming itself isn't smooth) then the texture was probably moved off the graphics card and into main memory beforehand and is just then being paged back onto the graphics card. If it's something else, the causes/solutions may be more complex.Also, you don't need to worry about manually pressing enter when posting. The board will handle all that automatically and it makes things slightly easier to read ;)   ;  The converse is truer. If you have largeish textures and don't use mipmapping, you could see a dramatic loss of speed. Texture sampling is one of the more expensive things you can do, so keeping more of it in the cache (by using smaller versions when able) is a big win.My grass implementation makes a second LOD out of "fins" and the texture for those needs detail from the alpha channel. I had to turn mipmapping off for this stage to keep the shaders accuracy working and my frame rated dropped from around 100 to around 80 purely as a result. And the textures in question are fairly small to begin with.Any jerking you're seeing is probably down to beat frequencies as you're rendering flat out? Putting vsync on is the correct way to stop that.   ;  Thank you for the answers. The jerking in the minimal-test-app really stops in fullscreen (vsync'ed) mode. The problem in the main app may lie somewhere else.   