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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2
votes
1answer
51 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
39 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
34 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
votes
0answers
45 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
votes
1answer
37 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 ...
1
vote
1answer
75 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
107 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
vote
1answer
44 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
71 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
votes
2answers
117 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 ...
0
votes
1answer
70 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 ...
0
votes
0answers
37 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 ...
1
vote
2answers
69 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
147 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
182 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
votes
1answer
34 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
89 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
43 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
127 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
96 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
votes
1answer
56 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
325 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
vote
0answers
139 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
165 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
votes
1answer
28 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
vote
2answers
98 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
votes
0answers
43 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
1answer
51 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
26 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
52 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
67 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
118 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
73 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
75 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
vote
0answers
41 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 ...
2
votes
1answer
61 views

How can I use shaders in Unity to write a scientific computing program?

I want to write a GPU shallow water code on Unity3D. For sure, performance matters a lot. I've done this before using DirectX and C++. But for a couple of reasons I want to redo it in Unity3D. I ...
5
votes
3answers
259 views

How to pass rendered frames from OpenGL to DirectX 11?

I have a dll that does some rendering using OpenGL. I need to render it to a texture and use that texture in direct x 11. My current attempt has been to render the OpenGL to a texture on one ...
1
vote
1answer
75 views

Version 320 is not supported, SDL C++

I have the following four lines before I create the window. SDL_Init(SDL_INIT_VIDEO); SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE); ...
0
votes
1answer
219 views

OpenGL won't interpret attributes correctly when trying to apply textures

I'm going through open.gl tutorials. I'm at the point where I want to apply textures. The tutorial first introduces texture coordinates to the vertices[] array, and then adding the corresponding in, ...
2
votes
1answer
74 views

OpenGL not rendering textures

i'm using OpenGL 2.1 with SDL2.0 and i'm trying to render a texture, using this steps: load the image: Image* image = new Image(); image->image = SDL_LoadBMP(path.c_str()); if ...
0
votes
1answer
86 views

Earth and sun - How to make the sun revolve around the earth in the following code?

I want to imitate the planetary system with Earth and Sun drawn as solid spheres on the same window. I have drawn the two: the earth as the bigger sphere and the sun as the smaller sphere. Now I want ...
1
vote
0answers
89 views

dFdx and dFdy implementation details

I've been trying to understand the details of dFdx and dFdy since I'm trying to implement MSAA on a compute shader. The best description I've found is here: dFdx and dFdy on the cpu //T is any ...
1
vote
0answers
41 views

Consistent Shadow Map Filtering

I want to filter my shadow map generated by PSSM, but the problem is that I have a inconsistent filter size. The problem is that the shadow map sources rotate to find the best fit for the camera ...
1
vote
0answers
42 views

glTextImage2D with GL_UNSIGNED_BYTE giving weird results while with GL_FLOAT just works, driver bug?

Update: OK, not being able to see the textures loaded by FreeImage was just one of the common mistakes when using modern OpenGL. My texture loading code did not set GL_TEXTURE_WRAP_S/T and ...
2
votes
1answer
83 views

Slick2d fullscreen with black bars

NOTE: I am moving this question here from Stack Overflow because I feel it belongs better on this forum. I am deleting the original question from Stack Overflow. I'm working on a game in Slick2D and ...
1
vote
0answers
73 views

OpenGL RayCasting and Intersection with plane

I have been trying for a couple of days to raycast. I have a Renderable/Texture/Primitive/Whatever placed in the WORLD at 0.0f,0.0f,0.0f, and when I click the mouse I want to know at what X,Y ...
1
vote
2answers
57 views

opengl z index changing does not zoom in

I am making a simple opengl application where I have a cube and I want to move forward to it with the glTranslate3d function, where I change the z index. One would expect the object to get bigger ...
1
vote
1answer
93 views

How can I make terrain texturing look detailed both close-up and far away?

I attempting to make my game have very detailed textures, and in general look pretty. However, I'm having some issues with that. Let's take a look at a rock texture close up: Picture. As you can ...
2
votes
1answer
40 views

Shaders wont bind to the uniform block

I'm having an issue with interface block binding. Example shader: const char* vertexShader = "#version 330 core\n" "uniform globalMatrices" "{" " mat4 ...
3
votes
0answers
84 views

Is there a 3d game engine without a built-in physics engine? [closed]

I know about jMonkeyEngine, Ardor3D, etc. Yes, I've also heard of LWJGL and OpenGL (the both are essentially the same, though) but neither of them really suit me. I don't want to deal too much in the ...