Questions tagged [vertex-buffer-objects]

17 questions
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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, &VAO); glBindVertexArray(VAO); …
juztcode
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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 vertices in a buffer object and bound it with a vertex…
2
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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); glDrawElementsBaseVertex(GL_TRIANGLES, meshIndicesCountList[x],…
2
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1 answer

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, when you call glBufferData with a NULL pointer,…
Whiteclaws
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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 are visible at any one time, would it be better…
Mark
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glTexCoordPointer output not as expected

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 texture generation: glGenTextures( 1, &tex…
tester
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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 the scene anymore unless I set the option…
Tare
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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 data.The only way it can get performance gain is…
undefined
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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 looked at this and followed the recommended stuff…
Burf2000
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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?
clamp
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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; data[1][0] = px2; data[1][1] = py1; data[2][0] =…
Jorgusss
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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 squares, leaving an empty space. if I reduce the…
George
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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 parallel with z-axis. But when the program runs, floor…
Shan-Hung Hsu
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LWJGL Cannot use offsets when Array Buffer Object is disabled

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.OpenGLException: Cannot use offsets when Array Buffer…
nedb
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Properly update vertex buffer objects

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 having unique vbo float *vertex_array; float…
Antiusninja
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