SRGB color space is commonly used by screens, i.e., a color picked in GIMP is in sRGB space, but shading calculations assume linear space.
#Opengl 3.3 glfw tutorial windows#
Culling and depth buffer is enabled as before, but we also enable multisampling (in the OpenGL 1.1 part we did not use it as on Windows the symbol is not exported) and sRGB rendering. This explicit state approach will be used throughtout the tutorial. The initial state setup is slightly different, especially there is no clear color present as we will use the color directly when calling the clear buffer function. Notice, the gladLoaderLoadGL function must be called after we have OpenGL context, in our case after the call to glfwMakeContextCurrent. I used glad as loader, but there are many alternatives available. Since the OpenGL on Windows comes only as version 1.1, the newer functions must be loaded during runtime from vendor's dynamic-link library. OpenGL 3.3Īgain, the window is created by GLFW, but this time the version is set to 3.3 with core profile that is set as forward compatible. The library we use in the next part for handling transformations uses operator overloading and thus reads more like a math. Warning, the transformations are applied in bottom to top order that can be confusing. The render loop is barebones, it clears color and depth, sets up transformation matrices, executes the display list, and flips the frame on VSync. Moreover, display lists are commonly used as an optimization to avoid both the CPU overhead from a large number of function calls and to keep the geometry in the fast GPU memory. I used display list to better mirror the more modern OpenGL approach we discuss later. Then the clear color is set and culling and depth buffer enabled.
#Opengl 3.3 glfw tutorial code#
In the code GLFW creates windows with OpenGL 1.1 version note that the version is specified before call to glfwCreateWindow. The code for the tutorial can be downloaded here. Shaders for the second part of the tutorial are located in the res folder. The debug build has all paths set and should build without issues. Both files have associated projects in the Visual Studio solution file. The file src/main_gl11.cpp uses OpenGL 1.1 and the other file src/main_gl33.cpp uses OpenGL 3.3 core profile. This tetrahedron is orbited by a perspective camera. The example renders tetrahedron with three single color faces and one face with interpolated colors from the corners. This debugger allows to inspect the OpenGL state, reports errors, shows the textures or depth buffer, visualizes meshes, and more. The choice of core profile (without the legacy cruft) not only helps to avoid land mines, but allows use of a debugger such as RenderDoc. As a target, I chose OpenGL 3.3 core profile instead of Direct3D 12, Metal, or Vulkan to avoid making the step too large. This tutorial aims to fill the gap between the fixed-function world and the world of buffers and shaders. However, the API is far from the GPU hardware architecture and the industry has been moving to more low level and programmable APIs. With display lists it can even scale to relatively large meshes. OpenGL 1.1 is a great API for teaching basic graphics, such as rendering meshes, coloring and shading, and texturing. Migrating from Fixed-Function OpenGL 1.1 to OpenGL 3.3 Core