Questions tagged [opentk]

OpenTK is a C# library that wraps OpenGL, OpenCL and OpenAL.

Filter by
Sorted by
Tagged with
0
votes
0answers
19 views

Why does this order of Quaternion multiplication not introduce roll into my fps-style character controller?

I'm working on an OpenGL based project (in C#), employing Quaternions to rotate my camera I first tried to: ...
1
vote
1answer
307 views

Vertex Skinning, Bone matrices question

I'm creating a model/animation viewer in C# using OpenTK for a game's models. Before stating my problem I want to describe a bit what I've accomplished so far in case I'm fundamentally missing ...
0
votes
0answers
20 views

RayCasting implementation not working with camera rotations

I've followed several guides for a custom implementation of a raycasting algorithm for picking objects in my opengl application. This is my unproject function ...
0
votes
0answers
12 views

Graphing 10 sets of Data

I have 10 sets of data saved in arrays. For example A1 = [1,2 ,3], A2 = [5,6,7]...etc. I am using OpenTk GameWindow to plot it as I have a big data set (10million+ per data set). For now I know how to ...
0
votes
1answer
56 views

C# NanoVG Transparency issue

Hi I'm trying to change from Cairo (2D Vector image library) to NanoVG. I'm using C#, openTK and Nano.VG.NET to make my game. I'm having issues with alpha? Transparency/Blending is an issue… Here ...
0
votes
1answer
49 views

uniform matrix not being assigned to shader

im trying to apply a rotation matrix to my shader and when i try to set it and mult it in the shader my triangle doesn't render my drawing code: ...
0
votes
1answer
582 views

Multiple glControl on same winform is not working - OpenTK C#

I have to show frames from two cameras in two openGl control separately at same time. For that I have put two opengl control in my form and pass those frames to opengl accordingly. But when running ...
0
votes
1answer
227 views

OpenGL frustum extraction

I'm trying to extract frustum planes from the camera. The algorithm is simple: create clip to world space matrix (inversed projection * inversed view) multiply clip point by clip to world matrix ...
0
votes
1answer
185 views

OpenTK OpenGL wierd camera look

I am trying to implement a simple camera mouse look. ...
0
votes
0answers
598 views

Greedy Meshing : Slow to rebuild when updating chunk

I've a problem with my voxel based game. The game is sliced into chunks (Like Minecraft), each chunk is 16x256x16 blocks. When I started the project, I used a basic culling system when hidden blocks ...
1
vote
1answer
172 views

OpenGL Texture from Raw Data Not Rendering Correctly

Starting off the class in question is here: ...
1
vote
1answer
2k views

Input in OpenTK

How to use Input in OpenTK 1.0? There is not much info around, some classes are unfinished. What I want to achieve, is to be able to use input not only in OnUpdate function, but also in other classes ...
0
votes
1answer
85 views

How can I load a texture from VBO?

I already have the .png file in my project, and the .png file has the "Embedded Resource" and "Do not copy" settings. The game runs fine - nothing throws an error, but the game does not show ...
0
votes
2answers
805 views

Opentk Textured Full Screen Quad

I want to display a texture on a full screen quad. What I get is a completely green quad and after a week of debugging I cannot understand why. I am currently using OpenTK 1.1.2225 and Magick.NET-Q16-...
0
votes
2answers
105 views

Multiple Indices Problem

Recently, I've been trying to use COLLADA files in OpenGL. The problem that a lot of people before me have run into is COLLADA's ...
0
votes
4answers
1k views

Missing triangles in model

I am having an issue where triangles in a model aren't being shown. The left is wireframe, the right is the finished image. For some reason a bunch of the triangles aren't being shown. The project ...
1
vote
2answers
228 views

Point[] and Tri not “could not be found”

Hi I'm trying to learn how to load a .obj file using OpenTK in windows Forms. I have seen a lot of examples out there, but I do see almost everyone uses ...
0
votes
1answer
856 views

OpenGL: I only see one square instead of a cube / giving information to vertex shader

I am new to OpenGL and tried to follow this tutorial. I use C# and OpenTK. So I translate the C++ Code from the Tutorial: My C#-Code: ...
5
votes
2answers
546 views

Trying to implement forward rendering in OpenGL

I'm working on implementing forward rendering in my 2D engine, as far as I'm aware everything should be set up correctly, I've ran into some issues earlier but I'm sure I've fixed those at this point. ...
0
votes
1answer
2k views

OpenTK Ray Picking

I just can't get ray picking to work (I need to drop old working faedback mode, and replace it with color pick, but because my scene can have up to 300K+ objects it is reasonable to filter (it's a ...
2
votes
1answer
2k views

OpenGL: Draw an arrow

I'd like to know how to draw an arrow to represent a vector position, length and direction. The issue is that I can't quite find an easy way to know the location and rotation of the triangle ...
2
votes
1answer
296 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 ...
-1
votes
3answers
582 views

Multiple rendering back ends architecture

so I've been thinking about designing a rendering engine with multiple back ends in C#. Well, let me rephrase; I wish to design an engine that can be easily extended upon to support multiple back ...
0
votes
1answer
1k views

How do I enable FSAA in OpenTK?

All I could find about it is this question, but GraphicsMode alone doesn't enable anti-aliasing: ...
1
vote
0answers
1k views

Play streaming sound in OpenTK?

What's the simplest way to make a sound stream from disk and play in OpenTK?
0
votes
1answer
590 views

OpenTK Terrain - Triangle strip issue

I'm currently trying to render terrain in an OpenGL application I'm making (using OpenTK in C#). Something really odd is happening and I'm not sure why. Here is the code I use to load my terrain from ...
0
votes
3answers
306 views

The largest vector in an array

I'm working on a game engine in C# at the moment and I've come across a matter I find confusing. I need to know how to get the maximum three component vector in an array. There is a method in OpenTK ...
7
votes
2answers
2k views

How do I reconfigure my GLES frame buffer after a rotation?

Note: In order to keep the question as simple as possible, I am actively changing the body of the question to reflect the current state of affairs, instead of adding stuff at the bottom. I am ...
0
votes
1answer
143 views

glClearBuffer takes 1 second on a Geforce 9500GT

These 2 lines (in C# using OpenTK) seem to cause 1 second lag every frame on a machine with a Geforce 9500 GT ...
3
votes
1answer
398 views

Turning On/Off Vsync no longer working when rendering to an offscreen buffer

I have this reaallly strange issue that as soon as I render to an offscreen framebuffer I am no longer able to toggle VSync while my application is running. I am using OpenTK as the opengl wrapper, ...
1
vote
1answer
334 views

OpenGL scissor odd behaviour

I am currently developing a GUI app using OpenGL with OpenTK as interface in C#. The viewport is set to the entire window space (0,0,width,height) and an ortho transformation is applied like this: <...
0
votes
1answer
1k views

Read from OpenGL texture to Bitmap in C#

I want to read a texture pixels from texture id (associated with some FBO) to bitmap object in opengl (opentk) in c# But it throws an exception says: ...
1
vote
0answers
329 views

OpenTK Camera Rotation issue [duplicate]

I'm currently developing a 3D game engine in C# using OpenTK. I have basic game objects, and each game object has transform (translation, rotation and scaling). A game object can have components (...
3
votes
3answers
2k views

Using multiple indexes with buffer objects in OpenTK

I've got multiple buffers in OpenGL holding data on position, normals and texcoords. I also have an equal number of buffers holding distinct index data for each of those buffers. I quite like this ...
1
vote
1answer
1k views

C# OpenTK - Getting world coordinates of points that are altered by matrices

I have written a skeletal animation system for a game I am working on. To draw lines that represent a skeleton, I use the GL matrix, and multiply it by each bone a long the body. For example before ...
6
votes
1answer
6k views

Should I use retained mode or immediate mode

I'm trying to make a opengl wrapper for winforms(.net). Basically you code in gdi+ syntax but it gets rendered for opengl(using glcontrol of opentk). Which mode should I use for rendering ui? It has ...
1
vote
1answer
802 views

Incomplete rendering using OpenTK (VBO)

Using Assimp.net I did load obj file. assimp returns back Mesh object that contains vertexes, normals, faces, colors and texture. when I don't use VBO the object will load complete. like this : But ...
0
votes
2answers
597 views

2D HUD over 3D scene

I'm trying to create a 2D Heads up Display for my players in a 3D OpenTK environment. How I'm doing it is by drawing my 3D elements and then running this code. ...
1
vote
0answers
83 views

Cube Translation Looks All Wrong

I'm making a very simple cube in OpenTK and it seemed to be going fine until I tried to move it around. Moving it along the X Axis seems to elongate the cube, not the result I hoped for. My Vertex ...
1
vote
0answers
27 views

GL.BlendFuncSeparate(ArbDrawBuffersBlend) Enum has no members?

I want to use the function GL.BlendFuncSeparate but it seems that one of the enums used has no members. public enum ArbDrawBuffersBlend { } Is ...
1
vote
0answers
774 views

Rotating an object around it's centre in OpenGL

I'm writing small 3d viewer of models from .obj file. I have a car and I want to rotate car's wheels. I found a lot of good examples but I still have a problem: wheel rotates around point at the it's ...
2
votes
1answer
1k views

What's the DSA version of glTexImage2D?

I want to set the initial data of a texture in an OpenGL 4.5 program (using OpenTK.Next and .NET), utilizing the new Direct State Access methods. However, I cannot find a DSA version of ...
1
vote
1answer
120 views

Shader or No Shader?

I have a question about something I don't really understand. In OpenTK, should I have shaders? Is it frowned upon not to? What are the pros and cons of having shaders? Can I go perfectly fine without ...
0
votes
1answer
179 views

VBO Performance issues

I'm making a 2D Tile based game in OpenTK at the moment. Performance was really bad (laggy and slow) with direct drawing, so I switched to VBOs. The performance hasn't changed, it might even be slower ...
0
votes
2answers
614 views

How to use texelFetch

I'm trying to switch from using the GLSL texture() function in my shader to using texelFetch() because I want very little ...
3
votes
0answers
464 views

Enabling OpenGL lighting seems to disable blending

I have the following code to set up for some 2D drawing using OpenTK. I originally wrote it without any lighting considerations, but later added the lighting block. This version of the code uses ...
0
votes
1answer
468 views

Draw wrong faces in obj model with OpenGL VBO

I am trying to draw a 3D model from an .obj file, and have met big trouble. I think my model draws with wrong faces, but I can't understand why. Original model: This is my code for reading the ...
2
votes
1answer
9k views

C# OpenTK Text rendering

I've been looking everywhere for a solution on how to render/draw text for my 2D OpenTK-based game. Been trying quite a few QuickFont ones without success (either a AccessViolation exception or text ...
2
votes
1answer
687 views

glUniformMatrix4fv OpenTK equivalent

Very simple and quick question which surprisingly I couldn't find an answer to over the internet: what is the equivalent of glUniformMatrixfv for opentk? I've browsed all the 7 overloads of GL....
2
votes
1answer
749 views

Opentk hdr rendering with framebuffer white screen problem

I am trying to do hdr rendering with two shader programs: one simply draws a hdr texture on a fullscreen quad and the other one does tonemapping. I am trying either linear tonemapping ...