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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1answer
431 views

How to improve Batch Rendering to work with 3D skeletal animation data

I've implemented a batch rendering technique that is described in detail here: http://www.gamedev.net/page/resources/_/technical/opengl/opengl-batch-rendering-r3900 I'd like to extend it now to ...
2
votes
1answer
257 views

How can I implement a camera like the one in RotMG?

RotMG, an MMO top-down shooter, takes on a unique 2d-3d style, and has an intriguing camera; The game is obviously 3d, not simply isometric, and if you play the game and turn on camera rotation you ...
2
votes
1answer
764 views

Architecture to draw many different objects in OpenGL

I have some objects that I want to draw. I am not sure how I can create my architecture in a way where I can draw everything as fast as possible. As example: class MyObject { float[] vertices; ...
2
votes
1answer
547 views

OpenGL ES draw pre-rendered background onto depth buffer

I want to create a scene with 2D pre-rendered background and 3D models for characters (like those classic Final fantasy games). For the background, I have 2 textures: one to be displayed, with ...
2
votes
1answer
63 views

How to know when graphics driver or card changes

I'm about to start work on implementing GLSL binary shader compilation and I was curious how to handle the cases when the shaders need to be recompiled, such as when the driver (or perhaps even the ...
2
votes
1answer
61 views

Rendering a mesh in image viewport

I have a mesh made of nearly half to a one million vertices. I also have some 6-DoF camera poses around this mesh. At these poses I'd like to find out which of the 3D points of this mesh get projected ...
2
votes
2answers
384 views

Water silhouette shader using GLSL

I have this problem to solve using Cocos2d-x 3.x: In my game there is water represented by rectangle texture, modified by the code on the go. I also have a character moving around, rotating etc. I ...
2
votes
1answer
339 views

GLFW mouselook under OSX

I'm continuing to port an OpenGL app from Visual Studio 2012 to XCode 5. The only major issue I'm having is mouselook. It "doesn't work" under OSX (Mavericks). Here's the (pseudocode): ...
2
votes
1answer
229 views

Additive blending problems

I'm trying to get the blend of two images to work without luck. I have a render target on which I have an object, then I want to render again the same object in same position but with different ...
2
votes
1answer
194 views

What types of matrices are needed for game and graphics programming?

I am writing a 3D math library for general game development and want to know what type of Matrix classes I should include. Is just a 4x4 matrix enough, or must I provide 3x4 and dedicated rotational ...
2
votes
1answer
1k views

Reflection and shadows in OpenGL

I'd like to implement shadows and reflective surfaces in my OpenGL app. I already have ideas which I will provide below. But I would like to ask someone more experienced than me before I put too much ...
2
votes
1answer
506 views

How to create a regular grid of triangles correctly?

I am trying to create an terrain using opentk/opengl. I have a problem with the VBO/IBO. I think a picture of the problem is the best way to show it: I dont understand why the last triangle of a ...
2
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2answers
1k views

3D position to UV coordinates in fragment shader

I am interested in converting an arbitrary 3D position computed at run time in the fragment shader to its corresponding UV coordinates. Notice that the 3D position I am interested in is NOT a 3D ...
2
votes
1answer
2k views

Why do I get “function not supported” exceptions for OpenGL 3.2 functions using LWJGL?

I am currently having an issue trying to initialize a frame buffer using LWJGL. When I try to call GL32.glFramebufferTexture(int, int, int, int) it throws a "Function is not supported" error. I have ...
2
votes
1answer
160 views

Does Direct3D have hardware-dependant extensions like OpenGL?

I am not familiar with Direct3D and I want to know if it has hardware and vendor dependant functions like the extensions in OpenGL? A program written by a friend fails on certain computers while it ...
2
votes
1answer
502 views

Efficient way of loading wavefront models in openGL game

In my game, a RTS game, the units are all wavefront obj. all their animation frames are each seperate wavefront obj file. ie. without any skeletal animation; fully rigid models. So when many units are ...
2
votes
2answers
509 views

Batching and Z-order with Alpha blending in a 3D world

I'm working on a game in a 3D world with 2D sprites only (like Don't Starve game). (OpenGL ES2 with C++) Currently, I'm ordering elements back to front before drawing them without batch (so 1 element ...
2
votes
1answer
950 views

Assimp renders a partial amount of vertices

I'm building a 3D game, and i'm trying to load some assets with the nice Assimp library. The model should look like the one in the first picture, but instead, it takes the form of some kind of ...
2
votes
1answer
403 views

Do glColorMask and glDrawBuffer accomplish the same thing?

I'm doing a shadowmap pass (only storing depth values) so I set glDrawBuffer(GL_NONE) to disable color writing for the moment. Yet, I see some tutorials also do glColorMask(GL_FALSE, GL_FALSE, ...
2
votes
1answer
672 views

How can I render a single object that uses multiple textures?

I'm looking for a technique to render an object with multiple texture sources. One texture is static, the other is generated dynamically (it's a render target). For example, say I was rendering a TV. ...
2
votes
3answers
718 views

How can I apply a mesh distortion to walls like in Dungeon Keeper 2?

In Dungeon Keeper 2, the walls of the dungeon have different random shapes depending on its state (freshly dug or reinforced, and so on). They look like they are cubes of 3x3 vertices that have a ...
2
votes
1answer
660 views

Black or White Border/Shadow around PNGs in SDL/OPENGL

having the same issue as this: Why do my sprites have a dark shadow/line/frame surrounding the texture? however, when I do the fix suggested there (changing GL_SRC_ALPHA to GL_ONE) it just replaces ...
2
votes
2answers
3k views

Drawing multiple objects from one Vertex Buffer Object in OpenGL/OpenTK

I am trying to experimenting drawing method using VBO in OpenGL. Many people normally use 1 vbo to store one object data array. I was trying to do something quite opposite which is storing multiple ...
2
votes
1answer
1k views

Uncharted 2 tone mapping and an eye adaptation

I found an example of uncharted 2 tone mapping on this site. Here is the code: float A = 0.15; float B = 0.50; float C = 0.10; float D = 0.20; float E = 0.02; float F = 0.30; float W = 11.2; float3 ...
2
votes
2answers
348 views

Orthographic Zooming with 0,0 at top/left

I'm trying to implement zooming on my 2D game. Since it's using orthographic projection, I thought it would be easy to implement zooming. After looking around the internet, I found a bunch of ...
2
votes
1answer
104 views

Expandable player boundaries

I'm trying to plan how to implement non-fixed boundaries so the player can expand their controlled territory without using a tiled based system. Each pixel can be fought over for who controls it. I ...
2
votes
1answer
758 views

What happens when a texture is too large for a device

The question is two fold: What happens on a device when a texture is too large for it to handle? Will it crash or simply downsize it? In Unity if I use texture atlases of size 4k and then set ...
2
votes
2answers
217 views

.md5mesh normals are not smooth

I'm currently working on a project that requires me to load .md5mesh format and draw it. Following this link I've managed to load the mesh into the engine successfully, but a problem arises when ...
2
votes
1answer
669 views

Camera scrolling and game boundaries

I am making a platformer game in JBox2D and LWJGL that has a scrolling camera, but I have hit a wall with the boundaries of the camera. Essentially what I have right now is a Box2D world that is ...
2
votes
1answer
1k views

Heightmap and Textures

Im trying to find the "best way" to apply a texture to a heightmap with opengl 3.x. Its really hard to find something on google because tutorials are olds and they're all using different methods, im ...
2
votes
1answer
161 views

How to obtain touch events from a GL Viewport, not the whole screen?

Background I'm implementing viewport resizing in order for my game to maintain the same display ratio on all devices. However, I've found an issue with getting touch events. Basically, if my ...
2
votes
1answer
187 views

Manual GLU.gluUnproject

Before I used GLU.gluUnproject to calculate my picking ray in my OpenGL game. Recently I switched to my own calculated matrices, and now I can forget the gluUnproject. How can I calculate the picking ...
2
votes
2answers
332 views

How scanline rendering finds an intersection with an object

I'm a newbie with graphics and after I read many articles on the web I still don't understand how in rasterizing from a pixel coordinate like (0;0) on the screen the intersection with an object (let's ...
2
votes
1answer
546 views

Translating Viewmatrix is inverted, why?

So I've defined a Projectionmatrix, Viewmatrix and a Modelmatrix using OpenGL (LWJGL). But when I translate my Viewmatrix to +X it moves my object to the right (hence my camera is moving to the ...
2
votes
1answer
492 views

gbuffer - how to store an integer data

In a gbuffer I store a diffuse color in following texture: glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL); I want to store an integer data which ...
2
votes
1answer
1k views

HDR / Tone Mapping - choosing parameters

I implement HDR in my graphics engine (deferred rendering) based on this document: link I save a luminance in a texture (RGBA16F) this way: const float delta = 1e-6; vec3 color = texture(texture0, ...
2
votes
1answer
2k views

glsl 150 struct in uniform buffer object

Can I do this in opengl 3.2 / glsl 150? glsl shader: struct LightSource { vec4 ambient; vec4 diffuse; vec4 specular; vec4 position; vec4 direction; }; ... layout(std140) uniform ...
2
votes
1answer
375 views

How to transform a shadow map to camera view?

I'm making a rendering engine as a hobby to learn more about 3D. I have a deferred renderer with the G-buffer (color, normal and depth). I also have a lighting controller that uses only spotlights at ...
2
votes
1answer
394 views

Not repeating background in platformer [closed]

I need to make not repeating background for platformer. I can't find any description of implementation and I developed algorithm but I'm not sure that it's right. I can't load one big texture per ...
2
votes
1answer
3k views

Can I mix OpenGL and swing?

I'm working on a small game library for me and some people I know that just handles the window and nothing special that we weren't gonna use. I know how to use OpenGL and stuff I just don't like ...
2
votes
1answer
982 views

Octrees and Vertex Buffer Objects

As many others I want to code a game with a voxel based terrain. The data is represented by voxels which are rendered using triangles. I head of two different approaches and want to combine them. ...
2
votes
2answers
1k views

Raycasting mouse coordinates to rotated object?

I am trying to cast a ray from my mouse to a plane at a specified position with a known width and length and height. I know that you can use the NDC (Normalized Device Coordinates) to cast ray but I ...
2
votes
2answers
2k views

Quaternion based rotation and pivot position

I can't figure out how to perform matrix rotation using Quaternion while taking into account pivot position in OpenGL.What I am currently getting is rotation of the object around some point in the ...
2
votes
1answer
2k views

Can't use SFML sprite drawing and OpenGL rendering at the same time

I'm using some SFML built in functions to draw sprites and text as an overlay on top of some OpenGL rending in an SFML RenderWindow. The opengl rendering appears fine until I add the code to draw the ...
2
votes
1answer
134 views

Uniform not being applied to proper mesh [closed]

Ok, I got some code, and you select blocks on a grid. The selection works. I can modify the blocks to be raised when selected and the correct one shows. I set a color which I use in the shader. ...
2
votes
1answer
405 views

OpenGL 3+ Range Picking

How do I perform range picking in the latest OpenGL version? By range picking I mean selecting all objects which are picked using a selection rectangle, like in an RTS game. For single object picking ...
2
votes
1answer
876 views

OpenGL: Move camera regardless of rotation

For a 2D board game I'd like to move and rotate an orthogonal camera in coordinates given in a reference system (window space), but simply can't get it to work. The idea is that the user can drag the ...
2
votes
1answer
348 views

Is there any reason not to save skinning animation data in texture?

I have thought about saving animation data in texture. I think I can save shader parameter setting and interpolation cost in CPU, and also enable animated instancing. But I couldn't find no text ...
2
votes
1answer
546 views

Finding a suitable axis-angle to avoid gimbal lock

In OpenGL the camera faces the -z axis with the +y axis pointing up. I am using quaternions to represent the orientation of my objects (which works well) and am trying to do the same for the camera. I ...
2
votes
1answer
1k views

Procedural terrain using 3D noise

I'm coding a procedural terrain generation based on this article from GPU Gems 1. But using CPU (not GPU). I'm stuck at generating the procedural terrain. I just can't figure out how make a 3D ...