opengl-4

If I create a double-precision vertex buffer, for example: GLuint vertBuffer, spanBuffer, spanCount, patchSize, program; // already setup glUseProgram (program); glEnableClientState (GL_VERTEX_ARRAY); glBindBuffer (GL_ARRAY_BUFFER, vertBuffer); glVertexPointer (3, GL_DOUBLE, 0, 0); glPatchParameteri (GL_PATCH_VERTICES, patchSize); glBindBuffer (GL_ELEMENT_ARRAY_BUFFER, spanBuffer); glDrawElements (GL_PATCHES, spanCount * patchSize, GL_UNSIGNED_INT, 0); How do I access the double precision data in my vertex shader? Should I be able to do this? // GLSL VERTEX SHADER #version 410 in dvec4 gl

Originally using glDrawElementsInstancedBaseVertex to draw the scene meshes. All the meshes vertex attributes are being interleaved in a single buffer object. In total there are only 30 unique meshes. So I've been calling draw 30 times with instance counts, etc. but now I want to batch the draw calls into one using glMultiDrawElementsIndirect . Since I have no experience with this command function, I've been reading articles here and there to understand the implementation with little success. ( For testing purposes all meshes are instanced only once ). The command structure from the OpenGL

I've looked everywhere, but there seam to be no ruby binding that would allow to create OpenGL 3/4 context. It do not have to be complete OpenGL binding library, just portion that creates OpenGL context. Update: If I'm desperate enough I'll do partial glfw ruby binding with ruby ffi. So pls save me from that ;) I have written a library that can create an OpenGL 3 or 4 context on most platforms (provided it is supported). It's called Ray . You don't have to use its drawable system or DSL, you can just use it to create a window and an OpenGL context. Ray::GL.major_version = 3 Ray::GL.minor

I had some 3D code that I noticed wouldn't render in a strict core profile but fine in a "normal" (not explicitly requested-as-core-only) profile context. To isolate the issue, I have written the smallest simplest possible OpenGL program drawing just a triangle and a rectangle: I have posted that OpenGL program as a Gist here . With the useStrictCoreProfile variable set to false, the program outputs no error messages to the console and draws a quad and a triangle as per the above screenshot, both on an Intel HD OpenGL 3.3 and on a GeForce with OpenGL 4.2. However , with useStrictCoreProfile

I'm following the steps in HOWTOBUILD.txt . I have the necessary files for glfw built already. For the first time, the linker is complaining about glfw. After searching, it seems I need to link against gl3w see this link . I've generated the static libs for gl3w . Now, I've opened a new project and included the path to include , see the below picture. For the linker, I've linked against glfw3dll.lib gl3w.lib opengl32.lib and included their path. If I run the sample from the first chapter, main.cpp #include "sb7.h" class my_application : public sb7::application { void render(double currentTime)

What are the diffences between "Shader Storage Buffer Objects" (SSBO) and Image load store operations When should one be used and not the other? They both can have atomic operations and I assume they are stored in the same type of memory. And regardless if they are stored in the same type of memory, do they have the same performance characteristics? edit: the original question was asking between SSBOs and Uniform buffer objects, it was meant to be between SSBO and Image load store. The difference between shader storage buffer objects and image textures and why one would want to use them is

I'm trying to understand Textures, Texture Units and Samplers in OpenGL 4.5. I'm attaching a picture of what I'm trying to figure out. I think in my example everything is correct, but I am not so sure about the 1D Sampler on the right side with the question mark. So, I know OpenGL offers a number of texture units/binding points where textures and samplers can be bound so they work together. Each of these binding points can support one of each texture targets (in my case, I'm binding targets GL_TEXTURE_2D and GL_TEXTURE_1D to binding point 0 , and another GL_TEXTURE_2D to binding point 1 ).