glsl

I am trying to use the OpenGL Shading Language (GLSL) version 1.5 to make vertex and geometry shaders. I have learned that in GLSL version 1.5, the built-in variables like gl_ModelViewProjectionMatrix are deprecated so you have to pass them in manually. If I have already set the modelview and projection matrices (using gluLookAt and gluPerspective for example) then how do I get the matrices to pass into the vertex and geometry shaders? I've done some searching and some sites seem to mention a function glGetMatrix() , but I can't find that function in any official documentation, and it doesn't

The popular way of using GLSL shaders in WebGL seems to be to embed them in the main html file. The vertex and fragments shaders are embedded in tags like: <script id="shader-fs" type="x-shader/x-fragment"> This is the same convention I see in the WebGL samples in the Mozilla Developer Network page. This works fine for simple apps, but when you have a complex app with a number of shaders, the html file gets cluttered. (I keep editing the wrong shader!) Also if you want to reuse your shaders, this scheme is inconvenient. So I was thinking about putting these shaders in a separate XML files and

Is there a way to efficiently change hue of a 2D OpenGL texture using GLSL (fragment shader)? Do someone have some code for it? UPDATE: This is the code resulting from user1118321 suggestion: uniform sampler2DRect texture; const mat3 rgb2yiq = mat3(0.299, 0.587, 0.114, 0.595716, -0.274453, -0.321263, 0.211456, -0.522591, 0.311135); const mat3 yiq2rgb = mat3(1.0, 0.9563, 0.6210, 1.0, -0.2721, -0.6474, 1.0, -1.1070, 1.7046); uniform float hue; void main() { vec3 yColor = rgb2yiq * texture2DRect(texture, gl_TexCoord[0].st).rgb; float originalHue = atan(yColor.b, yColor.g); float finalHue =

I would like to leave OpenGL's lights and make my own. I would like my shaders to allow for a variable number of lights. Can we declare an array of uniforms in GLSL shaders? If so, how would we set the values of those uniforms? Yes this is possible. You declare uniform arrays similar to how you'd do it in C, e.g. uniform float v[10]; Then you can set their values using glUniform{1,2,3,4}{f,i}v GLfloat v[10] = {...}; glUniform1fv(glGetUniformLocation(program, "v"), 10, v); Yes it is possible to declare an array of uniforms in GLSL shaders. Just google "glsl uniform array" for some examples

My code approaches GLSL shader management in the way, that it creates each shader and the associated program and deletes each shader and program. I recently read http://www.opengl.org/wiki/GLSL_Object and there it is stated that: The shader object, due to being attached to the program object, will continue to exist even if you delete the shader object. It will only be deleted by the system when it is no longer attached to any program object (and when the user has asked to delete it, of course). Do I get this correctly, if I call glDeleteShader() on the shader object after linking to the

I am trying to render a 2D(Screen coordinated) sprite in OpenGL. Yet, when I compile it, it does not show up. I see that the code is fine (There are not even any shader compilation errors nor any other errors). I also have also the matrices set up(which I doubt is causing the problem, and that's where starts the CONFUSION!!) Here is the source code, by the way(without debugging, to make it short):- main.cpp // Including all required headers here... #include <iostream> #define GLEW_STATIC #include <GL/glew.h> #include <GLFW/glfw3.h> #include "SOIL2/SOIL2.h" #include <glm/glm.hpp> #include <glm

I was having previously already the problem that I wanted to blend color values in an image unit by doing something like: vec4 texelCol = imageLoad(myImage, myTexel); imageStore(myImage, myTexel, texelCol+newCol); In a scenario where multiple fragments can have the same value for 'myTexel', this aparently isn't possible because one can't create atomicity between the imageLoad and imageStore commands and other shaderinvocations could change the texel color in between. Now someone told me that poeple are working arround this problem by creating semaphores using the atomic comands on uint