Tagged Questions

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

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0
votes
1answer
45 views

GLSL: Vertex attribute to int

I'm trying to write a shader which renders a multitextured geometry wihout rerendering the geometry with each texture. In my test I'm not using textures, I just convert the texture index to a color ...
1
vote
1answer
153 views

How do I call OpenGL methods that require pointers in C#?

I have found the following C++ code in this tutorial to draw a triangle with OpenGL 4: float points[] = { 0.0f, 0.5f, 0.0f, 0.5f, -0.5f, 0.0f, -0.5f, -0.5f, 0.0f }; GLuint vbo = 0; ...
1
vote
1answer
56 views

Opentk LookAt() and 'eye' argument rotating

I'm trying to create rotating camera, which looks down by 45 deegre like this: However my code for rotating eye vector is not working properly and I achieve vertical rotation, when it should be ...
-2
votes
0answers
25 views

Mouse Selection custom shape opengl render select

I'm using openTk for a my project. I have serious problem with mouse selection. I tried unsuccessfully a lot of examples found on the web. So, I have to draw a grid with some coils (custom cylinders ...
2
votes
1answer
91 views

OpenTK GL.DrawElements is never called

I found this C++ code here. It draws simple rectangle. Works great. #define GLEW_STATIC #include <iostream> #include <glew.h> #include <freeglut.h> const GLchar* vertexSource = ...
1
vote
1answer
73 views

OpenGL - Buffer Usage

I am currently working on a little OpenGL project. At the moment I am trying to find a good solution for rendering multiple objects. I have set up a terrain with its own buffers, which works just ...
1
vote
1answer
107 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 ...
7
votes
1answer
264 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 ...
1
vote
1answer
732 views

OpenGL - Calculating camera view matrix

Problem I am calculating the model, view and projection matrices independently to be used in my shader as follows: gl_Position = projection * view * model * vec4(in_Position, 1.0); When I try to ...
1
vote
1answer
86 views

Why are my objects rotating with my camera?

I am working with this C# library that wraps OpenGL. I am trying to understand why my objects in the scene are rotating as I yaw my camera (view matrix). Here is an image where I have 4 separate ...
4
votes
1answer
112 views

OpenGL - What steps to take to correctly set up an Uniform Block Array

I have managed to get uniform blocks to work, but I seem to make something wrong when trying to setup an array of uniform blocks. Assume this glsl: layout(std140, binding=1) uniform LightingBlock ...
-1
votes
2answers
192 views

How to translate along Z axis in OpenTK

I am playing around with an OpenGL sample application I downloaded for Xamarin-Android. The sample application produces a rotating colored cube I would simply like to edit it so that the rotating cube ...
4
votes
1answer
212 views

OpenGL rendering looks squeezed

I am rendering bunch of cubes of unit size, but for some reason they look like they are squeezed a bit in the screen-space y axis. Why is this? My projection matrix: Projection = ...
0
votes
2answers
213 views

OpenGL UseProgram() fails

I have a rather strange exception on my application using OpenTK on Linux (ArchLinux with Mono 3.2.8) with GL.UseProgram(). I wrote a class to combine multiple files to one program: public sealed ...
2
votes
0answers
290 views

OpenGL drawing 500k triangles [closed]

I want to render big, izometric 2d map (using ortho projection). I am using OpenTK and aiming for OpenGL 3.3. Perfect option would be to draw 512x512 map of tiles, which is 262144 blocks -> 524288 ...
1
vote
1answer
337 views

GLSL - std140 uniform block - fields(vec, float, mat4) always 0.0

Ok, First of all, if just use uniforms everthing works like it should. Switching to uniform blocks nothing goes, as all values look like 0.0. I tested this with various if-then-else stuff within the ...
0
votes
1answer
133 views

How do I prevent clicking at the end of each sound play in OpenAL?

I have put together a basic sound handler class for use in my game. It uses OpenAL. It's a simple method at the moment to play sounds - here's an extract from a switch block: case "EATEN_PILL": ...
2
votes
1answer
180 views

How do I animate pieces between puzzle states?

I'm developing a simple C# puzzle game as a learning exercise, using OpenTK. It's similar to Puzzles and Dragons' puzzle part: The aim is to match 3 pieces to remove them. Removed pieces are replaced. ...
0
votes
0answers
391 views

Use opentk window handle to host wpf control - Monogame

well my boss asked me to try and get wpf controls rendered in Monogame. From what I understand this was easly doable in Xna, however in monogame it fails. Is there any way to make the window hadle ...
1
vote
2answers
226 views

Why swapping buffers takes different amounts of time?

When my program starts, almost nothing is on screen, just couple of lights and spheres. My FPS is at ~50. The Speed measurements looks like this: UpdateFrame took 0 ms Clearing lights queue: 0 ms ...
2
votes
1answer
252 views

Incorrect lighting results with deferred rendering

I am trying to render a light-pass to a texture which I will later apply on the scene. But I seem to calculate the light position wrong. I am working on view-space. In the image above, I am ...
1
vote
1answer
202 views

Understanding implementation of glu.PickMatrix() [closed]

I am working on an OpenGL project which requires object selection feature. I use OpenTK framework to do this; however OpenTK doesn't support glu.PickMatrix() method to define the picking region. I ...
1
vote
2answers
1k 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 ...
0
votes
0answers
267 views

OpenTK (OpenGL) Rotation around fixed axes?

How would I go about rotating things in 3-dimensional space along fixed axes? As OpenTK only seems to have rotation that modifies the other rotation, as in X affects Y & Z Y affects Z Z affects ...
0
votes
2answers
498 views

Translate extrinsic rotations to intrinsic rotations ( Euler angles )

The problem I have is very frustrating: I am using the Jitter Physics library which gives Quaternion rotations, you can extract the extrinsic rotations but I need intrinsic rotations to rotate in ...
0
votes
0answers
198 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
1k views

Draw quad with OpenGL VBO using OpenTK

I'm trying to learn how to use VBO (Vertex Buffer Objects) by putting together a simple program that draws a quad to the screen using OpenTK (C# OpenGL bindings). Unfortunately I'm not seeing ...
-1
votes
1answer
344 views

Using Shader causes triangle to disappear

The following is my rendering code. Private Sub GameRender() GL.Clear(ClearBufferMask.ColorBufferBit + ClearBufferMask.DepthBufferBit) GL.ClearColor(Color.SkyBlue) ...
4
votes
1answer
230 views

Upload vertex data for particles

I am kind of beginner with opengl. I am using point sprites (currently without any texturing) for my particles. I seem to fail to get them uploaded to the GPU memory correctly. I have readed lots of ...
0
votes
1answer
81 views

Normals not rotated correctly

While rendering a cube to the gbuffer (diffuse, normal, depth) I noticed something odd when applying rotations. I build a world matrix for the cube as follows: Yaw = Yaw % MathUtil.PI2; Pitch = Pitch ...
1
vote
3answers
2k views

How can I convert screen coordinatess to world coordinates in OpenTK?

I'm making a windows forms application with opengl view. I need to get the mouse coords converted to the opengl world coords. Well, my Y coord gets converted wrong. It's hard to explain, so here is ...
4
votes
1answer
109 views

What OpenCL video cards (or FPGAs) features are needed for high speed multiplication?

I'm benchmarking some cryptographic related software and am looking for video cards that are better at parallel multiplication vs parallel addition. Is there any prior work that would graph video ...
-1
votes
1answer
578 views

Problem rendering VBO [closed]

I'm developing a game engine using OpenTK. I'm trying to get to grips with the use of VBO's. I've run into some trouble because somehow it doesn't render correctly. Thus far I've used immediate mode ...
1
vote
2answers
171 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 List, and Point[]. Code example show these ...
2
votes
4answers
2k views

Is OpenTK Dead?

Looking at OpenTK, I notice some disturbing signs: The last news item was posted on December 31st, 2010 The main forum gets about one post a day On SourceForge, the last nightly build was in March, ...
0
votes
2answers
1k views

OpenTK 2D Engine [closed]

I'm looking for a 2D gaming engine for C#/Windows. OpenTK seems reasonable, albeit made for 3D. I didn't find anything (other than an old thread from 2008) that talks about a 2D game engine. Are ...
1
vote
1answer
369 views

Does OpenTK work in Windows 8?

While looking up OpenTK, I found a couple of references to threads that talk about Windows 8 support: This one from 2011 claims that OpenTK works on a Win8 preview A newer one from 2012 leaves the ...
1
vote
2answers
375 views

I enabled and setup glBlendFunc, but my texture has a white outline. What am I doing wrong?

You can see most of my source code in this question: Instead of the specified Texture, black circles on a green background are getting rendered. Why? Now I have the problem, that my texture has a ...
3
votes
2answers
213 views

Instead of the specified Texture, black circles on a green background are getting rendered. Why?

I'm trying to render a Texture via OpenGL. But instead of the texture black circles on a green background are rendered. (They scale, depending what the rotation of the texture is) Example: The ...
2
votes
1answer
164 views

Why do I have to divide the origin of a quad by 4 instead of 2?

I'm currently transitioning from C#/XNA to C#/OpenTK but I'm getting stuck at the basics. So I have this Sprite-Class: public static bool EnableDebugDraw = true; public float X; public float Y; ...
0
votes
4answers
481 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
1answer
218 views

OpenAL seems to ignore sound attentuation/orientation for long sounds

I don't know how else to describe it in the title, sorry. My sound engine currently works perfectly with listener positioning and sound positioning to create the attentuation and panning effects. At ...
2
votes
3answers
2k views

C# 2D Game Library?

I'm looking for a C# 2D game library based on something like OpenTK which wraps OpenGL for C# Basically something like Slick2D (2D game library for Java) which is based on LWJGL which is an OpenGL ...
0
votes
2answers
842 views

Can't render to FBO using a shader

I've added functionality so that I can render to a framebuffer (for post-processing and stuff). I can successfully render to my framebuffer and then render that framebuffer, but anything with a ...
1
vote
1answer
618 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 ...
1
vote
1answer
1k views

Why doesn't my texture display with this GLSL shader?

I am trying to display a DXT1 compressed texture on a quad using a VBO and shaders, but I have been unable to get it working. All I get is a black square. I know my texture is uploaded properly ...
1
vote
1answer
330 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 ...
13
votes
3answers
5k views

How do I implement a quaternion based camera?

UPDATE The error here was a pretty simple one. I have missed a radian to degrees conversion. No need to read the whole thing if you have some other problem. I looked at several tutorials about this ...
1
vote
2answers
816 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 ...
2
votes
2answers
191 views

Collisions between players at spawnpoints

I am working on a FPS/MMORPG and ran into a problem at spawnpoints, when I enabled collision detection between players. Neither player would be able to move if both spawned at the same time, because ...