OpenTK is a C# library that wraps OpenGL, OpenCL and OpenAL.
5
votes
1answer
82 views
Dual paraboloid shadows on GLSL
I'm trying to port an XNA example to OpenTK + OpenGL, I found it here http://graphicsrunner.blogspot.com.es/2008/07/dual-paraboloid-shadow-maps.html
But I'm having a really hard time, I think my maps ...
0
votes
1answer
64 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 ...
1
vote
0answers
9 views
CanDraw in large hierarchical scene with rotation
I've been assigned to write small simulation visualization, that contains thousands of cubes (I know you heard that before). Now I'm working on optimization of stuff that takes place there, but ...
0
votes
0answers
66 views
Camera rotation destroy scene objects orientation
I fight with that for some time and searching internet but I don't have any answer for my problem. In few words i want to have orbiting camera on screen and objects which I want also rotate ...
2
votes
0answers
122 views
Cannot convert bitmap to texture [closed]
I'm doing a little C# / OpenGL project and I can't manage to load textures properly.
So here is my texture class :
public class Texture
{
public String Filepath;
private int TextureID;
...
1
vote
1answer
264 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 ...
1
vote
1answer
97 views
OpenGL why point's size stay the same while zooming/unzooming
i'm currently working on a game engine for a college's project. While implementing some debug tools I came across a little problem. When i'm drawing point on the ModelView Matrix the point's thickness ...
1
vote
1answer
99 views
Legal Implications of using Openal in Opentk Commercially
Myself and my friend are currently creating a game, which we plan on selling upon its completion. We are using opentk.
I read over this: http://www.opentk.com/node/532 , and it pretty well describes ...
0
votes
0answers
102 views
Matrix, vector multiplications in OpenTK
I developed a 3d model viewer in c++ with OpenGL, and in c# in OpenTK. Both are using the same shader, but the output from OpenTK is not correct. I read that OpenTK is row major order, and OpenGL is ...
1
vote
0answers
80 views
Incorrect Texcoords for Bitmap Font? [closed]
I am writing some code to display text using a bitmap font. However, when I run my game to see my results, I am greeted with a blank screen. I changed the texture to pure white to see if it was even ...
0
votes
1answer
138 views
OpenGL not rendering full scene, it is a mystery [closed]
I am trying to draw a scene in the sort of style of mock vector graphics. I've helped on a 2D game before with GLSL, but I tried to keep a simple approach to this project since I'm working by myself, ...
0
votes
1answer
258 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:
/* Hintergrundfarbe */
...
0
votes
1answer
172 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 ...
2
votes
1answer
343 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;
...
2
votes
1answer
681 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
1answer
229 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
101 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 ...
2
votes
1answer
297 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
722 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
3k 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
102 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
399 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
389 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
259 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
420 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
435 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
716 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 ...
2
votes
3answers
379 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
280 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.
...
1
vote
2answers
310 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
473 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
274 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 ...
2
votes
2answers
2k 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
2answers
799 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 ...
1
vote
0answers
344 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
2k 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
388 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
282 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
91 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
4k 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
121 views
What OpenCL video cards (or FPGAs) features are needed for high speed multiplication? [closed]
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
819 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
200 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 ...
3
votes
4answers
3k 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
429 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
571 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
264 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
181 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
684 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 ...
