17 questions
2
votes
2
answers
654
views
Unable to obtain buffer object data through glGetBufferSubData
I was hoping to make a tower of hanoi game using opengl. Eventually i came up to the problem of processing & transfering data from one buffer object to another.
I have successfully stored my ...
6
votes
1
answer
4k
views
how does a VBO get attached to a VAO
VAO being Vertex Array Object and VBO being Vertex Buffer Object. The calls for creating and binding/unbinding VAOs and VBOs have a general format as given below:
GLuint VAO, VBO;
glGenVertexArrays(...
- 1,431
1
vote
1
answer
507
views
Culling off-screen objects in OpenGL ES 2 2D
I'm playing about with OpenGL ES 2.0. If I'm working with a simple 2D projection, if I have a large 2D grid of vertices which are pretty much static (think map tiles), of which only a small proportion ...
- 1,894
2
votes
0
answers
285
views
OpenGL VAO + multiple VBO - theory - batch render
I'm thinking about tweaking my current batch render. What I currently do is run a loop with command like this :
shader->setUniformValue("mvp_matrix", matrix * geo[x].geoMatrix);
...
- 1,076
1
vote
1
answer
225
views
glTexCoordPointer output not as expected [closed]
I am trying to use glDrawElements , glTexCoordPointer and glTexImage1D to create a 1D texture, render a surface dataset and color the vertices according to their height value.
GLuint tex = 0;
My ...
- 425
1
vote
1
answer
2k
views
OpenGL VBO orphaning implementation
I'm currently working on a sprite renderer whose data changes every tick, so I've been looking for ways to stream a buffer object, I came across buffer orphaning... which confused me a bit.
Firstly, ...
- 968
1
vote
0
answers
395
views
Why does open scene graph only render if UseVertexBufferObject is enabled?
I have written a program with OpenSceneGraph (interfaced into Qt Gui) at work and all was fine. Now that I took the program home (i.e. I got the source code home and compiled it at home), I don't see ...
- 635
-1
votes
1
answer
87
views
Modern Modelling Formats that Support Vertex Buffers
Are there any modeling formats that directly support Vertex Buffer Objects?
Currently my game engine has been using Wavefront Models, but I have always been using them with immediate mode and display ...
- 4,448
1
vote
1
answer
838
views
opengl es2:Advantages of using vertex buffer objects(VBO)
I use glVertexAttribPointer to load my vertex data each frame(~242kb) it takes about 8ms.Will I gain any performance increase by employing VBO?I think the answer is NO since I still have to load whole ...
- 685
0
votes
1
answer
816
views
How to add objects to buffer? opengl
In this program I want to draw polygons.
Firstly I made sth like that:
GLuint VertexArrayID;
example of drawing polygon:
if (figure == RECTANGLE)
{
data[0][0] = px1; data[0][1] = py1;
...
- 7
0
votes
0
answers
173
views
Large Vertex Data Buffer
I'm trying to draw a lot of squares by loading vertex data (position and texture coordinates) into a VBO. My issue is when I try to load all of these vertices, for some reason it skips over some ...
- 3,060
0
votes
1
answer
1k
views
OpenGL: try to draw lines using VBO(vertex buffer object), it doesn't display
I try to switch my openGL code from using display list to using VBO.
In the code, I tried to draw a green-grid floor, which is composed by green lines in parallel with x-axis and green lines in ...
- 137
0
votes
1
answer
1k
views
LWJGL Cannot use offsets when Array Buffer Object is disabled [duplicate]
I have looked at a lot of posts, and cannot find what is wrong with my code.
I have bound my VBO however it doesn't work and gives me this error:
Exception in thread "main" org.lwjgl.opengl....
- 706
0
votes
2
answers
2k
views
Properly update vertex buffer objects [duplicate]
I've got a training app written in winapi
So, I've got GL initialized there and I've got node-based system, that can be described by couple of classes
class mesh
{
GLuint vbo_index; //this is for ...
- 167
1
vote
1
answer
483
views
Android OpenGL ES 2.0 : VBA and VBO with different positioned objects
So I am working on a project which is a bit like Minecraft in that there are thousands of cubes.
I hit a huge performance hit quite early on and so started looking at ways to improve the FPS
I first ...
- 5,223
0
votes
1
answer
359
views
In OpenGL ES, can multiple programs have the same VBO used and bound to their attributes?
I have two programs which I am switching between. I loaded my position data up in a VBO and then set up my vertex attribute arrays for my first program. When I switch to the second program and attempt ...
- 1,710
1
vote
1
answer
39
views
Lowest OpenGL ES version to use Vertex Buffer Objects
What is the lowest possible android and opengl es version that i can go and still be able to use vertex buffer objects?
- 34.2k