textures

Are glTexImage2D and glTexSubImage2D the only ways to pass a buffer of pixels to a texture? At the moment I use in a setup function glTexImage2D passing null as the buffer, and then on the render loop I call glTexSubImage2D with the new buffer data on each iteration. But knowing that the texture will not change any property such as the dimensions, is there any more efficient way to pass the actual pixel data to the rendering texture? Sergey K. In modern OpenGL there are 4 different methods to update 2D textures: glTexImage2D - the slowest one, recreates internal data structures.

I'm using the tutorials on http://arcsynthesis.org/gltut/ to learn OpenGL, it's required, I have to use it. Mostly I want to apply the textures from Tutorial 15 onto objects in tutorial 7 (world with UBO). For now it seemed like the textures only work when mipmaps are turned on. This comes with a downside: The only mipmap used is the one with an index of zero, and that's the 1 colored 1x1 pixel one. I tried setting the minimum level of a mipmap higher or turning off mipmaps entirely, but even that doesn't fix thing, because then everything turns pitch black. Now I'll list the most important

Almost exact duplicate question: OpenGL font rendering using Freetype2 . I am trying to render text in my OpenGL program using FreeType2 (2.5.3), based on this tutorial: http://en.wikibooks.org/wiki/OpenGL_Programming/Modern_OpenGL_Tutorial_Text_Rendering_02 , using the same structs as Bentebent did in his question (above). I am having the same problem he was having with rectangles showing up instead of legible characters (even using the correct GL_TEXTURE0 parameter for glActiveTexture() ) For example, rendering green strings "Hello" and "World" below it gives me this: As with Bentebent,

Do I have to delete all the textures I created (using glDeleteTextures) before the program exists, or does OpenGL delete the textures by himself? Kaiged Depending on what manages your OpenGL context, you may not need to delete the textures. For an example, see this question . There does seem to be consensus, though, that it is good to clean up after yourself, but be careful when using C++ RAII to do so! If a C++ object that manages an OpenGL object via RAII is created or destroyed without an OpenGL context, undefined behavior will occur. See: The Object Oriented Language Problem The OpenGL API

OpenGL has array textures , denoted in shaders by specific sampler types: sampler2DArray array_texture; But GLSL also allows samplers to be aggregated into arrays: sampler2D array_of_textures[10]; Are these two features related to each other? How are they different? Let's understand the distinction by analogy. Samplers in GLSL are like pointers in C++; they reference some other object of a given type. So consider the following C++ code: int* pi; std::array<int, 5>* pai; std::array<int*, 5> api; pi is a pointer to a single object of type int (let's ignore the fact that technically it could be a