You’re right, the vertex shader is executed for each vertex. A vertex is composed by of or several attributes (positions, normals, texture coordinates etc.). On the CPU side when you create your VAO, you describe each attribute by saying “this data in this buffer will be attribute 0, the data next to it will be … Read more
If I imagine that the GL_TEXTURE_2D is a picture’s frame hangging on the wall and textureId is the real picture, Actually a very good analogy 🙂 so, what GL_TEXTURE0 and glActiveTexture are? Think about a wall with multiple picture frames, the first frame being labeled GL_TEXTURE0, the second GL_TEXTURE1 and so on.
According to this article it seems that now RDP handles newer versions of Direct3D and OpenGL on Windows 10 and Windows Server 2016, but by default it is disabled by Group Policy. I suppose that for performance reasons, using a hardware graphics card is disabled, and RDP uses a software-emulated graphics card driver that provides … Read more
Yes! you can use the desktop window as the window passed to OpenGL- as long as you don’t try to display anything on it 😉 Just Call GetDesktopWindow and pass the result as an argument when creating new OpenGL window.
They are located at /System/Library/Frameworks/OpenGL.framework/Headers. To include them, just use: #include <OpenGL/gl.h> #include <OpenGL/glu.h> #include <OpenGL/glext.h> #include <GLUT/glut.h> etc. Make sure to link against the appropriate frameworks, eg) cc <your_file.c> -framework GLUT -framework OpenGL for OpenGL and GLUT
The OpenGL wiki gives a good definition: A Shader is a user-defined program designed to run on some stage of a graphics processor. History lesson In the past, graphics cards were non-programmable pieces of silicon which performed a set of fixed algorithms: inputs: 3D coordinates of triangles, their colors, light sources output: a 2D image … Read more
I’m going to argue that the most efficient approach will be in drawing a single “full-screen” triangle. For a triangle to cover the full screen, it needs to be bigger than the actual viewport. In NDC (and also clip space, if we set w=1), the viewport will always be the [-1,1] square. For a triangle … Read more
In OpenGL, lines are rasterized using the “Diamond Exit” rule. This is almost the same as saying that the end coordinate is exclusive, but not quite… This is what the OpenGL spec has to say: http://www.opengl.org/documentation/specs/version1.1/glspec1.1/node47.html Also have a look at the OpenGL FAQ, http://www.opengl.org/archives/resources/faq/technical/rasterization.htm, item “14.090 How do I obtain exact pixelization of lines?”. … Read more
How to get GHCi to load the opengl package under GHC 7.6.1 x86-64 Windows 7?
It creates a projection matrix, i.e. the matrix that describes the set of linear equations that transforms vectors from eye space into clip space. Matrices really are not black magic. In the case of OpenGL they happen to be a 4-by-4 arrangement of numbers: X_x Y_x Z_x T_x X_y Y_y Z_y T_y X_z Y_z Z_z … Read more