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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Implement steamworks_sdk in OS X

Well, I'm using OS X and using as compiler 'g++' and well editing in VIM. I wan't to use the steamworks_sdk. I can use the all the code that is in 'sdk/public/steam' and well, compile all. But I ...
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1answer
110 views

Java - LWJGL OBJ Loader with Materials not rendering

So I successfully loading my obj file but I obviously want to get materials on it. I added the vt(texture) to the OBJLoader and the Model.render but still rendering textureless. I have exported the ...
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1answer
50 views

Terminology for the way Transformation Matrix Data is treated

I recently asked a question at math stack exchange and realize a similar questions is more suited for this forum, but the original is here: ...
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2answers
53 views

c++ Opengl handle elements drawn

I am currently working on a game and I want to know if there is any way of handling with the elements i am drawing . For example : if i draw in a loop 100 cubes , how can i show / hide the cube number ...
4
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1answer
149 views

Rotate billboard towards camera

I'm trying to create a particle system in OpenGL, and as such I need to use billboards. I need these billboards to face the camera at all times. The tutorials I've been following only rotated the ...
3
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1answer
72 views

How to determine what color will be written into single pixel framebuffer?

I thinking about rendering into single pixel (1x1) framebuffer. For example we have two triangles which covers whole NDC area, one is green second red. What color will be written to 1x1 framebuffer? ...
6
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1answer
179 views

How can I extrude a regular, grid-based 2D shape to 3D?

I have a list of vertex coordinates which encircle several 2D areas. Orthogonal lines only, but not necessarily convex areas... similar to PCB traces of conductive copper areas. I want to draw them ...
4
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1answer
65 views

What is the fastest way of drawing simple, textured geomtries and keeping the depth test?

I'm looking for a fast way to draw simple 3D geometries - that will consist of up to 10 vertices. Each of them will have a texture (though varying between geometries). I also want to store the ...
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0answers
48 views

OpenTK crashes with Mono

I've implemented OpenTK as a secondary renderer which would let me support Mac/Linux only to realize that for some reason, even without any modifications (new MonoGame project), the application would ...
3
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1answer
106 views

VBO rendering crashed with glDrawArrays

I'm playing around in LWJGL3 and I'm experiencing an issue regarding glDrawArrays. At glDrawArrays the JVM crashes. I'm using modern OpenGL and therefore I have my own shaders and matrix ...
1
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1answer
83 views

OpenGL Picking: How to avoid entities?

I have a terrain and entities(npc, house...). I'm able to convert screen coordinates to world coordinates with the glReadPixels function: glReadPixels(mousePosition.x, mousePosition.y, 1, 1, ...
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0answers
72 views

Point Light shows black box & rect (PointLight not working) - libgdx 3D

I am creating a 3d scene currently a box and rect, and trying to enable lighting. When i create a PointLight and add it to Environment everything turns to black color? all i want to do is ...
3
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0answers
69 views

Draw Edges in OpenGL

I use blender game engine, and blender use openGL for graphics. How can I draw lines around all 3D objects? Would this be a job for a filter? Mainly, I want my end result to look drawn. I found this: ...
3
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0answers
37 views

When I add in Java transformationMatrix I can't see images? [closed]

When I add in Java transformationMatrix I can't see images moving but when I remove it I can see why and how to fix it? Any ideas how to fix it? My Renderer class: public class Renderer { ...
0
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2answers
78 views

Inverse of perspective matrix, for what?

I dont understand for what i need the inverse of the perspective Matrix in Computer Graphics and how do i calculate it?Maybe someone has an explanation for me.
2
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1answer
63 views

glViewport Problem

I am using glViewport() to render a 1024x1024 shadow depth buffer for a game that is using a 1000x600 game window. Under normal circumstances it works fine, however when I am running Bandicam to ...
2
votes
1answer
82 views

Finding pitch/yaw values from lookat vector

I have a camera class that contains a position, a pitch, and a yaw (the pitch and the yaw correspond to y and x rotation values). I want to implement a lookAt function that takes a vector and the ...
1
vote
1answer
42 views

Vector out of range (Batch rendering & opengl)

So ive (tried to) implement a batch rendering system, and at the for loop the error pops up and I'm not shure what ive done wrong. Any suggestions to improve the system would be much appreciated. ...
2
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0answers
77 views

Texture coordinates for custom geometry in SceneKit ios9

I am trying to texture the a custom plane shape I created in scenekit on iOS9. I need the texture to spread out and stretch over the entire surface. I have a vertex and fragment shader on an ...
2
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1answer
41 views

(GLSL) Lighting code outputting a black quad

So, ive been transitioning to modern opengl recently and it's going rather well. But alas, something must go wrong. As the titel says, all I'm getting is a completely black quad. (Ive double checked ...
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1answer
96 views

Bullet Physics / OpenGL Meshes Not Colliding

This is for a school project, and I'm having a bit of trouble with Bullet acting strangely. I have an OpenGL project with Bullet Physics library working with Assimp model loaders and Magick++ ...
4
votes
1answer
117 views

How do I use openGL shader to reproduce this Photoshop implementation?

Here are my Photoshop actions: step1 - convert the current image into gray step2 - use the default parameters, as showed in the screenshot step3 - use the 『Hue/Saturation』 to convert the grey ...
1
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1answer
68 views

Converting normalized device coordinates to world space coordinates flipping my sprites

I'm trying to convert my game's camera system to use world space coordinates rather than OpenGL's default normalized device coordinates, however in doing so my sprites are being rendered improperly as ...
2
votes
1answer
109 views

Transparency sorting in 3D world with different render types

I am rendering a world, object, and models from an older game format. The world is presented in a BSP tree so I can quickly iterate through. The opaque surfaces are rendered front to back. Then ...
2
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2answers
174 views

MSAA/ CSAA / FXAA How to set the mode in OpenGL?

I'm learning OpenGL and something I am stuck with is AA. Specially when I want to turn it on and off at runtime. I know that I can set the samplecount when I create a FBO and blit it over to the final ...
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1answer
80 views

Strange artifacting with textures (Pseudo 3D)

I'm using SFML to make a pseudo 3d engine (Technically not software rendered since SFML uses OpenGL) and things are going rather swimmingly, but then I tried to make another wall, the picture says ...
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0answers
41 views

Stencil buffer confuse

I was trying to make two object outline. One would color the object with orange and other with green. I just wanna know if is it possible to have two object outline at the same time because every time ...
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2answers
108 views

Section cut through (solid) geometry

I'm looking for image based (screen space) technique to render section cuts through arbitrary (solid) geometry. I found and studied image based CSG (Kirsch 05 / OpenCSG) but I found it to be perhaps a ...
3
votes
1answer
394 views

What is GLEW and how does it work?

I am looking for a beginner-friendly explanation. The official website's explanation is too short and lead me to more questions than answers: What is GLEW? GLEW developer's page says: The ...
4
votes
1answer
244 views

Hierachical Z-Buffering for occlusion culling

I'm reading the Occlusion Culling section in Real-Time Rendering 3rd Edition and I couldn't understand how it works. Some questions: How does having a "Z-pyramid" contribute? Why do we need multiple ...
0
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1answer
55 views

Wrong texture position on camera move

When in my game i move my character, the camera follows it. I have no problem drawing this char when it is moving or moving another char when the camera is still. Now, when i move both of them, the ...
1
vote
1answer
92 views

Is it ok to use polymorphism as a way of “interfacing” with objects in a scene? [closed]

I'm designing a class that holds values representing a 3D scene. This includes lights, cameras, meshes, materials, etc. The way how I'm setting it up is that each "thing" has a name. A camera has a ...
0
votes
1answer
47 views

Texture object and texture unit in GL

As I understand texture usage consist of two parts How to store this discrete data about texture internally. How much dimensions, channels, etc. How to fetch/sample/filter The question relative to ...
2
votes
1answer
144 views

How can I optimize block rendering in an OpenGL game?

I am working on a game with blocky graphics -- similar to Minecraft. My world generation algorithm is similar to the Diamond-Square algorithm. The terrain was initially too rough and uneven, so I ...
2
votes
1answer
251 views

GL_DEPTH_COMPONENT vs GL_DEPTH_COMPONENT32

I googled like crazy and checked the OpenGL documentations but I couldn't find out how the precision of a depth buffer created using GL_DEPTH_COMPONENT is chosen. As far as I know the precision is ...
0
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1answer
106 views

glDrawElements Crash

This is the "init" code of the Renderer class: glGenBuffers(1,&_idVBO); glGenBuffers(1,&_idEBO); glBindBuffer(GL_ELEMENT_ARRAY_BUFFER,_idEBO); glBindBuffer(GL_VERTEX_ARRAY,_idVBO); GLint lUV ...
4
votes
1answer
394 views

Can instantiated objects have different material/texture?

While I have some experience with simple 2D games, I am new to more process-demanding 3D games. One basic question that has been concerning me recently and for which I am having difficulties to find a ...
1
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0answers
319 views

LNK2019 unresolved external symbol __imp_ glDrawArrays@12 referenced in function _main [closed]

I try this code from tutorial for learn Modern OpenGL in Visual Studio 2015: http://www.opengl-tutorial.org/beginners-tutorials/tutorial-2-the-first-triangle/ With GLUT (from other tutorial), it ...
0
votes
1answer
350 views

Terrain shader from heightmap opengl GLSL

I generated a terrain from a heightmap and now I'd like to apply shader on it which can contain different textures, based on height but I can't adapt any online code to my project. This is the ...
0
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1answer
38 views

Generating Formulas for glDrawElements with Tile Grids

glDrawElements can be used to save you from uploading a lot of vertices to the GPU. Many 2D games use tiles, which are rendered in grids. I have done some experimenting with the indices array. For a ...
1
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2answers
112 views

OpenGL — Better to switch out material or shader for changing object colors?

I'm fairly new to shaders and OpenGL so bare with me please, I just want to make sure I'm doing it correctly! Now I'm using LibGDX in order to create a simple 3d diagram for my company. I have a few ...
0
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0answers
58 views

Framebuffer texture shows as blank white when rendered after TrueTypeFont

I have a working framebuffer class. However, when I render out the framebuffer after rendering text with Slick2D's true type font class, it is completely white. Below is all of the classes that are ...
1
vote
2answers
126 views

Cumulative transformation matrices for hierarchical object transformations

I'm having a small issue with my design for hierarchical 3D objects. I'll try to sum things up concisely. Every object has a vector3 for its position, scale, and rotation, as well as a std::vector of ...
1
vote
1answer
30 views

How can I move the camera directly under a certain plane?

I am attempting to render a "reflection" of a scene for water: To create this illusion, I need to render the scene from below, and then ignore all geometry below the water line. As such, I need ...
3
votes
1answer
60 views

What is causing my default libraries to conflict with OpenGL extensions?

So I'm currently following the tutorial for creating OpenGL programs on learnopengl.com,so I'm using GLFW, GLEW and the base library for OpenGL. However, when I go to build my code, I get a warning ...
2
votes
1answer
72 views

Giving values to uniform in OpenGL

First thing is that I know how to give values to uniforms in OpenGL. Second thing is that it is a question related to optimization and performance. The habit for changing the uniforms, we preferred ...
1
vote
3answers
127 views

Is there a way to get what pixel is being processed within the fragment shader?

In OpenGL, a fragment shader goes through each pixel, right? So is it possible (within the shader itself) to get what pixel it is processing and color each specific pixel?
3
votes
1answer
107 views

unable to render to multiple textures

I'm trying to make an example of deferred rendering. I'm trying to render to three separate textures the position, the normal and the color. Here is the setup : void setup() { //generate and bind ...
2
votes
1answer
96 views

How to blur image using glsl shader without squares?

I want to blur image with Gaussian blur algorithm. And I use the following shaders: Vertex shader attribute vec4 position; attribute vec4 inputTextureCoordinate; const int GAUSSIAN_SAMPLES = 9; ...
1
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0answers
56 views

Error “glGenBuffers is ambiguous” in Eclipse Mars [closed]

I have called a function, which is part of OpenGL correctly. uint vboId; glGenBuffers(1, &vboId); This is definitely correct because the program successfully runs. The error shown when I hover ...