OpenGL is a graphics standard and API which targets the desktop and workstation markets. It is designed to be easy to accelerate with dedicated computer hardware, and hence most implementations give greatly improved performance over traditional software rendering. Currently, OpenGL is used for ...

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249 views

Minecraft Modding - How do I use OpenGL stencil functions alongside the game's GlStateManager?

Note: I am using Minecraft Coder Pack 9.10 for game version 1.8.0 (official release). I am trying to make a multiline text field similar to the game's original net.minecraft.client.gui.GuiTextField. ...
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15 views

Project camera-to-pixel ray in world coordinates

I'm trying to implement a very simple ray tracing function but I have a problem with projecting the camera ray (from camera to pixel) to the world space. In the screen coordinates have the pixel ...
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1answer
88 views

Android OpenGL Sprite Component Pattern

Ok so I have a 2D OpenGL project that was originally a class assignment, and now I am using it to experiment with and to broaden my knowledge. Originally, I had been using the Normalized Devices ...
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36 views

More efficient way to load a sprite tilesheet(for animation) and how to avoid the texture dissappearing when it reloads? OpenGL, DevIL, C++

I'm not actually developing a game yet but I came here because I figured this would be the place to ask this kind of question. Issue 1: I have these tilesheets that I can load just find and they ...
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1answer
34 views

texelFetch weird behavior

I am writing an isometric game engine on OpenGL (version 3.3 specifically). For each wall tileset i have volume mask tileset for the wall relative volume coordinates. Volume mask looks like this: ...
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1answer
70 views

Issue with detecting collisions in Pong

I've been working on making Pong in OpenGL and SDL and currently have both paddles and the game ball set up properly. I have an Object (or Entity) class which is used to instantiate each of the ...
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0answers
19 views

My points are being draw in 2 locations?

Alright so I have an array with a bunch of vertices and I would like to draw it as line strips and as points. What I do is the following: glGenVertexArrays(1, &VAO); glGenBuffers(1, ...
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1answer
112 views

Should I always prefer a Uniform Buffer Object to a uniform variable for per-model uniforms in OpenGL?

I was looking for a way to update uniforms for all of my scene objects efficiently and I came across the following gamedev stackexchange question, where the top answer gives a bonus tip. It states: ...
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1answer
106 views

OpenGL Applications Bring computer to halt

Whenever I run any application that utilizes the OpenGL interface, my entire computer comes to a halt, but it doesn't do this when it utilizes the DirectX interface. I run both Linux (Ubuntu 15.10) ...
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1answer
65 views

Cannot connecting texture to heightmap using mapped uniform location

In my shader program, I have my attributes and uniforms added to a map for each. What I have displayed is a heightmap, but cant seem to connect the graphic texture to display. mUniformList ...
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16 views

GLSL `vec4` as return type syntax error? [on hold]

Here is my GLSL fragment shader code: #version 430 in vec3 fragPosition; in vec4 fragColor; in vec3 fragNormal; uniform int num_lights; layout(std430) buffer light { //... } vec4 lambert() { ...
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1answer
310 views

Trying to implement Camera

I'm trying to implement a Camera class in order to walk and look on the world as follow: #ifndef _CAMERA_H_ #define _CAMERA_H_ #include <glm\glm.hpp> class Camera { public: Camera(); ...
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1answer
593 views

OpenGL Tessellation makes point

A little problem with my tessellation shader. I try to implement a simple tessellation shader but it only makes points. Here's my vertex shader : out vec4 ecPosition; out vec3 ecNormal; void ...
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1answer
13 views

Should I use one GLSurfaceView.Renderer for each part of my game?

I am creating a small platformer-like game for Android using OpenGL. The game has 3 main screens/states: Main menu screen Level selection screen The game screen Currently I use a ...
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0answers
24 views

Environment mapping without cubemap (need coordinates projection)

I'm working on a project with C++ and glsl (4.1). I have implemented a mirror object which is a plane at height 0 that works as follow: I render the scene with a MVP computed such that the camera ...
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0answers
65 views

Transparent textures being handled oddly [closed]

In OpenGL why is it that when rendering transparent textures it changes the color values of all the pixels? Ex. when this transparent texture is rendered it comes out as this. Also if I change the ...
2
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2answers
65 views

Input before or after update/draw?

This is how I understood the game loop, and I wanted to know if I'm correct or not: 1) Draw/render -> input CPU | GPU ------------------ Update | Draw | Input | Rendering 2) Input -> ...
2
votes
1answer
188 views

Instanced rendering with ARB_vertex_attrib_binding

I'm trying to separate the vertex format specification from the vertex data. I was able to do that for the mesh vertices successfully. For instanced rendering I wanted to further separate the instance ...
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1answer
349 views

GL_SPOT_CUTOFF not working properly

I'm new to OpenGL. I'm studying OpenGL 2.1 and I'm trying to make a little program to test the GL_SPOT_CUTOFF property, but when I set a value between 0.0-90.0, the light doesn't work and everything ...
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1answer
38 views

glGenBuffers is NULL

I'm using GLEW 1.13.0, (GLUT), SDL2 and OpenGL 3.3 core. #include <GL/glew.h> #include <GL/glut.h> int main(int argc, char* args[]){ Engine::init(); // Initializes SDL_GL_* attributes ...
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2answers
229 views

Fragment shader compiling in webGL but not in OpenGL

I am programming in Haxe (language compiling to multiple platforms) and I have written some shaders. My fragment shader runs fine in html5, but when I try to compile for native (OS X and/or Neko, a ...
4
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1answer
161 views

OpenGL(Libgdx) - How to texture a 2D terrain surface?

I want to texture the surface of my terrain. I have created the ground mesh and surface mesh separately and everything is okay for ground mesh. But I couldn't texture the surface mesh correctly. As ...
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1answer
92 views

OpenGL App not setting cursor position appropriately

I have written a small application using OpenGL, and have implemented some rudimentary camera controls. Unfortunately, I cannot get the application to set my cursor position correctly. The cursor is ...
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1answer
91 views

When should i use GL_TRUE or GL_FALSE values?

When using GLboolean, should i just use true and false or should i use GL_TRUE and GL_FALSE, when should i prefer using GL_TRUE and GL_FALSE? or maybe i shouldn't care at all (Because both works)? ...
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21 views

What ways can I draw a single pixel or single fragment with Modern OpenGL? [duplicate]

I've been researching around the internet looking for ways to plot a single fragment or single pixel which ever is more usable for the case I will present now: I want to plot a pixel every click of ...
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1answer
431 views

OpenGL Fast-Object Instancing Error

I have some code that loops through a set of objects and renders instances of those objects. The list of objects that needs to be rendered is stored as a std::map>, where an object of class ...
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1answer
48 views

Rendering issues in Monogame when using shaders

I am currently fiddling with Monogame, trying to work with Shaders and I have encountered a really weird issue. If the first ever draw in the application's lifetime is with a custom shader all further ...
3
votes
1answer
65 views

Just how expensive is it to bind textures in OpenGL? (LibGDX)

I'm using LibGDX on top of OpenGL and currently my game engine does something along the lines of the following per frame Bind a terrain texture sprite atlas and a set of transparency masks in ...
3
votes
2answers
117 views

How to hide a post-processed mesh outline when/where the mesh is hidden

I'm working on setting up an active outline in my 3d engine, a highlight effect for selected 3d characters or scenery in the screen. After working with the stencil buffer and getting some ...
1
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1answer
35 views

How do I make my indices anti-clockwise, so I can cull triangles in OpenGL? (immediate mode)

At the moment, I'm attempting a basic game engine in OpenGL using immediate mode. I'm trying to render a cube. Cube is a class with the vertices, normals, and indices. Here is part of the Cube class: ...
0
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1answer
54 views

Getting the Right Vector from the Forward Vector

I'm currently working on a small Camera (ArcBall) and I finally am starting to understand how it will work. I will first create a basic View Matrix using a LookAt function. Then, I will send the ...
2
votes
1answer
2k views

Opengl-es picking object

I saw a lot of picking code opengl-es, but nothing worked. Can someone give me what am I missing? My code is (from tutorials/forums) Vec3 far = Camera.getPosition(); Vec3 near = ...
4
votes
2answers
160 views

Poor performance wth custom particle system in LibGDX

I'm using a custom particle system for my LibGDX / Java based game project (because I used Slick2D earlier on, need more parameters so I made my own and then ported). The system is fairly standard as ...
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1answer
124 views

OpenGL: How to map point inside frustrum to normal device coordinates (NDC)?

I read this article http://www.songho.ca/opengl/gl_projectionmatrix.html. It's explain how calculate projection matrix coefficients. But I completely can't understand how author perform mapping from ...
1
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1answer
77 views

Strange artifacts when using gl_FragCoord to access texels

I ran into a problem with using gl_FragCoord variable to access texels. The problem can be illustrated by following example: First I render a textured quad into texture of size (W, H) where W and H ...
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0answers
199 views

Artifacts rendering high-poly procedural meshes with OpenGL

I am having some issues when rendering some procedural generated meshes. There are some really wierd artifacts when rendering high-poly count meshes (not that much actualy). I have been able to ...
8
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2answers
524 views

stencil shadows - doom 3 engine - precision errors - shadow cracks - why?

I am testing the limits of the Doom 3 engine - in regards to maximum map size. I noticed some stencil shadow precision errors that become more pronounced when objects get further and further away ...
1
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1answer
509 views

OpenGL render to texture causing edge artifacts

This is my first post here so any help would be massively appreciated :) I'm using C++ with SDL and OpenGL 3.3 When rendering directly to screen I get the following result And when I render to ...
1
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2answers
538 views

How to reduce/remove graphical artifacts?

Question I'm working on a side-scrolling game that has a 2D grid for rendering to the screen. I'm using OpenGL, and I've optimized my game so that nothing invisible is attempted to be drawn. As of ...
2
votes
2answers
232 views

Deferred rendering: camera inside point light's sphere of effect

I'm trying out deferred rendering and I'm using the tutorials at http://ogldev.atspace.co.uk. I've got the basics working and I'm currently trying to implement the final step from tutorial 37 ...
20
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7answers
5k views

What advantage do OpenGL, SFML and SDL have over software rendering?

I started watching the Handmade Hero stream, where Casey Muratori creates a game engine without using frameworks or such. Yesterday I got to the part where he showed how an image is drawn onto the ...
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0answers
139 views

OpenGL ArcBall Camera

I'm currently working on a OpenGl Project and I have alot of difficulty understanding how arcball camera work. From what I have read online, all I have to do is to rotate a camera around a target and ...
0
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1answer
186 views

How to calculate spherical harmonic coefficients for indirect diffuse?

After reading the article "An Efficient Representation for Irradiance Environment Maps", I'm a bit confused as how to calculate the spherical harmonic coefficients. I'd like to generate these ...
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0answers
42 views

Renderering problem with flat terrain

i was testing out my game engine last night, but stumbled across this unexpected result. Here is a picture: As it appears, it is renderering 1 triangle and not renderering the other triangles. I ...
2
votes
1answer
115 views

How can I draw multiple lines connected via “nodes” in libgdx Scene2D?

I have two Vectors which indicate the ending points of each line. I am trying to draw similar lines to football formation lines like these. My main problem using ShapeRenderer is: ShapeRenderer ...
1
vote
3answers
75 views

Array Texture 2D with different sizes for the textures?

I'm making a 2D game engine, and I need a way to batch all textures into one so I only make one glBindTexture call throughout a scene. I am trying to use 2D texture arrays, but they only support ...
0
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1answer
147 views

Jittery Rotational Movement with Arcball implementation

I have an assignment where I need to implement arcball using Opengl (~2.0). I have it more or less implemented but I have a some problems/issues/bugs and I'm not sure whats either causing them or how ...
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1answer
64 views

How should I structure VBOs for my 2d world data?

My game is played on a fixed-size hex based arena, where each hex can be of a different type, and possibly contain some creatures/items/anything on it. When I started out, I got the advice to have a ...
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0answers
50 views

Problem with a TinyOBJLoader Renderer

I was working on implementing a renderer for SYOYO's tiny obj loader and when it came to testing time, it failed to render. Here is an image of the result: I believe that i have made the error with ...
1
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1answer
51 views

2D Sprite batching in OpenGL: How to send transformation data to GPU

OpenGL newbie here. So I'm trying to implement sprite batching to draw ~100 sprites per draw call. I've created a VBO that contains texture coordinates, vertex coordinates, color data (for tinting), ...