GLFW Mouse event lag with window drag

I am trying to drag an undecorated window in GLFW but am encountering some event lag, even though I am using glfwWaitEvents() I have a cursor position callback, and a simple loop: // register a cursor position callback glfwSetCursorPosCallback(win,...
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2017-09-13 19:09 (2) Answers

Trying to rotate a quad in 3d using Vispy

I am trying to rotate a textured quad in 3d using Vispy, but I can't seem to work it out. The code isn't producing any particular errors, but it's not rotating at all. I am new to Vispy, maybe I am missing some vital components in my code. Maybe some...
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2017-07-29 22:07 (1) Answers

Why doesn't this OpenGL example draw the triangle?

I'm trying to get a basic "draw a triangle on the screen" example working, but in Haskell with the gl and GLFW-b packages. My code is here: -- https://learnopengl.com/#!Getting-started/Hello-Triangle -- stuff from base import Control.Monad (when, ...
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2017-05-08 05:05 (1) Answers

Minimize mouse input lag on GL desktop app?

I think this is a common problem which relates to the OpenGL pipeline and how it queues rendered frames for display. How it looks like An extreme example of this can be seen in this video on Android. Mouse latency is present on the simplest deskto...
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2017-05-06 15:05 (0) Answers

Trouble compiling GLFW, undefined symbols

I'm currently reading this tutorial on OpenGL. I'm getting compile errors as follows: Undefined symbols for architecture x86_64: "_glfwInit", referenced from: _main in main.cpp.o "_glfwTerminate", referenced from: _main in main.cpp.o...
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2017-05-06 08:05 (1) Answers

opengl viewport in Mac with FMX delphi

I have designed an application in Delphi FMX that uses a new component based on class TPresentedControl. This component presents the output of opengl functions. (something like drawing in a viewport with opengl). In Windows application runs successf...
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2017-04-12 13:04 (0) Answers

OpenGL: PyCharm quit unexpectedly on Mac

I'm trying to run a project on Mac OS X that works on windows. The project is using the OpenGL and PyQt libraries. There seems to be a problem trying to use the OpenGL library. I downloaded a OpenGL demo of a helix that works. print("OpenGL: " + ...
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2017-04-10 19:04 (1) Answers

Render PNG images using OpenGL in Haskell

I am new to Haskell and I am building a chess game using OpenGL (using Graphics.UI.GLUT) for UI. I am trying to render PNG images for chess pieces. I read that images can be converted to TextureObject and then rendered, but could not find any helpfu...
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2017-04-07 12:04 (1) Answers

GLUT Error in Haskell Program

I'm using OpenGL with Haskell. I tried a sample program, it compiled successfully using ghc Compiler but when I run it, I get this error user error (unknown GLUT entry glutInit) I searched about this but most of the answers were related to this pr...
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2017-04-06 12:04 (1) Answers

Textures won't show on OpenGL and Xcode

My textures won't show up on screen, just the colored square. I collocated a condition and a cout sentence to let me know if the image is loaded on memory correctly. It does indeed, but texture won't show Why does this happen? Is there something I am...
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2017-03-26 07:03 (1) Answers

OpenGL - Sampler2D array in GLSL 120?

I'm working on a game engine, and I need to have an array of Sampler2Ds in my fragment shader to support multiple textures. On GLSL 130 and above it looks like this: uniform sampler2D textures[32]; Sadly, my graphics card is just the default Intel...
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2017-02-26 00:02 (1) Answers

glGenVertexArrays Mac OSX PyOpenGL

I'm trying to run glGenVertexArrays on PyOpenGL on my Mac (10.11.5). It is not finding it. The problem seems to be the version of OpenGL supported by my Mac (?). I've tried to research the issue but it seems that the documentation is written for eit...
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2017-02-19 11:02 (1) Answers

Haskell with OpenGL. (Unknown GLUT entry glutInit)

I need help getting OpenGL and GLUT to work using Haskell. Running a windows 10 system. I have installed the OpenGL package using cabal, but when I try to run the following program (and similar tutorial-like short programs): import Graphics.UI.GLUT...
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2017-02-06 17:02 (1) Answers

OpenGL VSync / NSTimer issues on macOS

I'm trying to set up a simple OpenGL game on macOS, using an NSTimer to set up a run loop as explained here. The idea is to create a repeating timer with a very small (~1ms) time interval and rely on vsync to regulate the frame rate. I'm setting my...
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2017-01-07 05:01 (1) Answers