我似乎在使用 VBO 在 OpenGL 中绘制对象时遇到了一些麻烦。我试图从以下位置复制示例:http ://www.opengl.org/wiki/VBO__-_just_examples (第 2 号),但我无法让飞机出现在屏幕上。
顶点.h:
#include <freeglut>
struct Vertex {
GLfloat position[3];
GLfloat normal[3];
GLfloat *uvs[2];
unsigned short uvCount;
};
三角形.h:
#include <GL/glew.h>
#include "Vertex.h"
class Triangles {
public:
Triangles(GLuint program, Vertex *vertices, unsigned int vertexCount, unsigned int *indices[3], unsigned int indiceCount);
~Triangles();
void Draw();
private:
GLuint program;
GLuint VertexVBOID;
GLuint IndexVBOID;
GLuint VaoID;
unsigned int *indices[3];
unsigned int indiceCount;
};
三角形.cpp:
#include "Triangles.h"
#include <stdio.h>
#include <stddef.h>
Triangles::Triangles(GLuint program, unsigned int *indices[3], unsigned int indiceCount) {
memcpy(this->indices, indices, sizeof(int) * indiceCount * 3);
this->indiceCount = indiceCount;
this->program = program;
glGenVertexArrays(1, &VaoID);
glBindVertexArray(VaoID);
glGenBuffers(1, &VertexVBOID);
glBindBuffer(GL_ARRAY_BUFFER, VertexVBOID);
glBufferData(GL_ARRAY_BUFFER, sizeof(Vertex) * vertexCount, vertices, GL_STATIC_DRAW);
GLuint attributeLocation = glGetAttribLocation(program, "position");
glEnableVertexAttribArray(attributeLocation);
glVertexAttribPointer(attributeLocation, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), (GLvoid *)(offsetof(Vertex, position)));
attributeLocation = glGetAttribLocation(program, "normal");
glEnableVertexAttribArray(attributeLocation);
glVertexAttribPointer(attributeLocation, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), (GLvoid *)(offsetof(Vertex, normal)));
glGenBuffers(1, &IndexVBOID);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, IndexVBOID);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(unsigned int) * 3 * indiceCount, indices, GL_STATIC_DRAW);
};
Triangles::~Triangles() {
glDisableVertexAttribArray(glGetAttribLocation(program, "position"));
glDisableVertexAttribArray(glGetAttribLocation(program, "normal"));
glDeleteBuffers(1, &VertexVBOID);
glDeleteBuffers(1, &IndexVBOID);
glDeleteVertexArrays(1, &VaoID);
}
void Triangles::Draw() {
glBindVertexArray(VaoID);
glDrawElements(GL_TRIANGLES, indiceCount, GL_UNSIGNED_INT, 0);
};
摘自 main.cpp(创建 triagle 对象):
Vertex vertices[4];
vertices[0].position[0] = -1;
vertices[0].position[1] = 1;
vertices[0].position[2] = 0;
vertices[0].normal[0] = 0;
vertices[0].normal[0] = 0;
vertices[0].normal[0] = 1;
vertices[0].uvCount = 0;
vertices[1].position[0] = 1;
vertices[1].position[1] = 1;
vertices[1].position[2] = 0;
vertices[1].normal[0] = 0;
vertices[1].normal[0] = 0;
vertices[1].normal[0] = 1;
vertices[1].uvCount = 0;
vertices[2].position[0] = 1;
vertices[2].position[1] = -1;
vertices[2].position[2] = 0;
vertices[2].normal[0] = 0;
vertices[2].normal[0] = 0;
vertices[2].normal[0] = 1;
vertices[2].uvCount = 0;
vertices[3].position[0] = -1;
vertices[3].position[1] = -1;
vertices[3].position[2] = 0;
vertices[3].normal[0] = 0;
vertices[3].normal[0] = 0;
vertices[3].normal[0] = 1;
vertices[3].uvCount = 0;
unsigned int **indices;
indices = new unsigned int*[2];
indices[0] = new unsigned int[3];
indices[0][0] = 0;
indices[0][1] = 1;
indices[0][2] = 2;
indices[1] = new unsigned int[3];
indices[1][0] = 2;
indices[1][1] = 3;
indices[1][2] = 0;
Triangles *t = new Triangles(program, vertices, 4 indices, 2);
创建着色器(GLenum,字符 *):
GLuint createShader(GLenum type, char *file) {
GLuint shader = glCreateShader(type);
const char *fileData = textFileRead(file);
glShaderSource(shader, 1, &fileData, NULL);
glCompileShader(shader);
return shader;
}
着色器加载:
GLuint v = createShader(GL_VERTEX_SHADER);
GLuint f = createShader(GL_FRAGMENT_SHADER, "fragmentShader.frag");
program = glCreateProgram();
glAttachShader(program, v);
glAttachShader(program, f);
glLinkProgram(program);
glUseProgram(program);
vertexShader.vert:
in vec3 position;
in vec3 normal;
out vec3 a_normal;
void main() {
gl_Position = vec4(position, 1.0);
}
片段着色器.frag:
in vec3 a_normal;
out vec4 out_color;
void main() {
out_color = vec4(1.0, 1.0, 1.0, 1.0);
}
如果需要更多代码,请告诉我。作为旁注,一切都编译得很好,我只是看不到我在屏幕上构建的飞机(可能是因为我没有使用颜色?)
我的OpenGL信息如下:
- 供应商:ATI Technologies Inc.
- 渲染器:ATI Radeon HD 5700 系列
- 版本:3.2.9756 兼容性配置文件上下文
- 扩展: extensions = GL_AMDX_name_gen_delete GL_AMDX_random_access_target GL_AMDX_vertex_shader_tessellator GL_AMD_conservative_depth GL_AMD_draw_buffers_blend GL_AMD_performance_monitor GL_AMD_seamless_cubemap_per_texture GL_AMD_shader_stencil_export GL_AMD_texture