vbo

问题 I am able to render the below points using the VBO and shaders in OpenGL 4.x. typedef struct Point { double x,y,z,w; }Point; std::vector<Point>vPoints; glBufferData(GL_ARRAY_BUFFER, vPoints.size()* sizeof(Point), &vPoints[0], GL_STATIC_DRAW); glVertexAttribPointer(0, 4, GL_DOUBLE, GL_FALSE, vPoints.size()*sizeof(GLdouble), (GLvoid*)0) How do we specify VBO to draw a line string using below variables typedef struct LineString { vector<Point> vPointList; }LineString; vector<LineString> vLines;

问题 Im creating a 2D SideScroller game for my thesis. For rendering the environment i want to use Vertex Buffer Objects. At home, everything works fine, but in University i get a similar error message: A fatal error has been detected by the Java Runtime Environment: EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x651e3435, pid=964, tid=2988 JRE version: Java(TM) SE Runtime Environment (7.0_55-b13) (build 1.7.0_55-b13) Java VM: Java HotSpot(TM) Client VM (24.55-b03 mixed mode, sharing windows-x86

问题 I've been trying to use Vertex Buffer Objects to save vertex data on the GPU and reduce the overhead, but I cannot get it to work. The code is below. From what I understand you generate the buffer with glGenBuffers , then you bind the buffer with glBindBuffer so it's ready to be used, then you write data to it with glBufferData and its done and can be unbinded and ready for use later with simply binding it again. However the last part is what I'm having trouble with, when I bind it after I

问题 I'm using the glDrawElements call with VBOs to render my scene. The scene is a cloth with vertices and texture coordinates - in this example, I'm rendering a flag. With my scene, the vertices are dynamic which means I need to write to a VBO every frame. Much of my processing is done on the GPU using CUDA, so I'm constantly mapping CPU memory to GPU memory. The texture coordinates, on the other hand, are static. In order to render with glDrawElements (as I understand it), I should interleave

问题 I am trying to solve a bug with my excercice of VBO/OpenGL, but after some hours (days), I am unable to found what is wrong. The problem is the windows stay black, the cube is not (correctly) drawn. - The OpenGL context seem to be correctly created for OpenGL 3.2 Vertex Shader: #version 150 core uniform mat4 RotationMatrix; uniform mat4 ProjectionMatrix; in vec3 in_Position; void main(void) { gl_Position = ProjectionMatrix * RotationMatrix * vec4(in_Position, 1.0); } VBO initialization: // <-

问题 I am trying to draw part of my tile image but I am getting GL_INVALID_VALUE error when I call glDrawElements function. There is no problem when I change this function with glDrawArrays. The problem is that the indices count parameter is not negative number. There is a code: #define BUFFER_OFFSET(i) ((char *)nullptr + (i)) #define VERTEX_ATTR_PTR(loc, count, member, type) \ glEnableVertexAttribArray(loc); \ glVertexAttribPointer(loc, count, GL_FLOAT, GL_FALSE, sizeof(type), BUFFER_OFFSET

问题 After doing some computation on the GPU I want to copy the results stored in the FBO to VBOs for rendering. The problem : It looks like some of the data is corrupted when I do the copy. I've already checked both buffers' format and size, and also checked that the data stored in the FBO is correct. Consider the following code that initializes the FBO: unsigned int verticesTextureId = AllocateTexture(GL_TEXTURE_RECTANGLE, mVBOSize, 1, GL_RGBA32F, GL_RGBA); CHECK_FOR_OPENGL_ERRORS(); unsigned

问题 EDIT: Working coded example by Apple found at this link: http://developer.apple.com/library/ios/#documentation/3DDrawing/Conceptual/OpenGLES_ProgrammingGuide/TechniquesforWorkingwithVertexData/TechniquesforWorkingwithVertexData.html After creating the vertices for a fixed grid of 200 x 200 squares, I render it by sending the vertices to the GPU using a VBO. How can I then update the colour of the vertices? The colour of hundreds of vertices will change frequently - every few frames. I

问题 I'm a little confused as to the proper usage of VBOs in an OpenGL program. I want to create a terrain paging algorithm, using a map called from a 4096x4096 greyscale heightmap as the "whole" map. From what I've read, each vertex stored in the VBO will take up 64 bytes. The problem I have is that most sources state that a single VBO should be between 1-4mb in size, and less VBOs is better. Yet according to my calculations, storing each vertex would take a total of about a gigabyte of data!

问题 The following Python program should draw a white triangle in the upper right quadrant of the window. import pygame from OpenGL.GL import * from ctypes import * pygame.init () screen = pygame.display.set_mode ((800,600), pygame.OPENGL|pygame.DOUBLEBUF, 24) glViewport (0, 0, 800, 600) glClearColor (0.0, 0.5, 0.5, 1.0) glEnableClientState (GL_VERTEX_ARRAY) vertices = [ 0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 1.0, 0.0 ] vbo = glGenBuffers (1) glBindBuffer (GL_ARRAY_BUFFER, vbo) glBufferData (GL_ARRAY