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我试图用一个简单的弹簧质量系统的动画开始学习现代openGL的。OpenGL的：两个顶点数组+双数组索引
我已经在我的课弹簧和质量，每次使用索引阵列中得出，当我这样做无论是单独他们都很好地工作。当我将两者都画在一起时，顶点位置都是错误的。我猜测它与我如何对顶点缓冲区和索引数组进行编号有关，但我不明白内部工作足以解决问题。
#include "Spring.hpp"
#include "ShaderPaths.hpp"
#include "atlas\gl\Shader.hpp"
#include "atlas\core\Macros.hpp"
#include <atlas/utils/Geometry.hpp>
const int NUM_VERTICES_PER_LINE = 3;
const int NUMFLOATSPERVERTICES = 6;
const int VERTEX_BYTE_SIZE = NUMFLOATSPERVERTICES * sizeof(float);
GLint numSpringIndices, numMassIndices;
#define NUM_ARRAY_ELEMENTS(a) sizeof(a)/sizeof(*a);
Spring::Spring() : anchorPosition{ 0.0f, 1.0f, 0.0f }, mPosition{0.0f, 0.0f, 0.0f} {
USING_ATLAS_GL_NS; //Short for atlas GL namespace
USING_ATLAS_MATH_NS;
glGenVertexArrays(1, &mVertexArrayObject);
glBindVertexArray(mVertexArrayObject);
ShapeData Spring = ObjectGenerator::makeSpring(anchorPosition, stretch, d);
ShapeData Mass = ObjectGenerator::makeMass(calculateConnectionPoint(anchorPosition), massWidth, massHeight);
ShapeData Triangle = ObjectGenerator::makeTriangle();
numSpringIndices = Spring.numIndices;
numMassIndices = Mass.numIndices;
//======= Spring Buffer ======//
glGenBuffers(1, &mSpringBuffer);
glBindBuffer(GL_ARRAY_BUFFER, mSpringBuffer);
glBufferData(GL_ARRAY_BUFFER, Spring.vertexBufferSize(), Spring.vertices, GL_STATIC_DRAW);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, VERTEX_BYTE_SIZE, 0);
glEnableVertexAttribArray(1);
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, VERTEX_BYTE_SIZE, (char*)(sizeof(float) * 3));
glGenBuffers(1, &springIndexBufferID);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, springIndexBufferID);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, Spring.indexBufferSize(), Spring.indices, GL_STATIC_DRAW);
//======= Mass Buffer ======//
glGenBuffers(1, &mMassBuffer);
glBindBuffer(GL_ARRAY_BUFFER, mMassBuffer);
glBufferData(GL_ARRAY_BUFFER, Mass.vertexBufferSize(), Mass.vertices, GL_STATIC_DRAW);
glEnableVertexAttribArray(2);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, VERTEX_BYTE_SIZE, 0);
glEnableVertexAttribArray(3);
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, VERTEX_BYTE_SIZE, (char*)(sizeof(float) * 3));
glGenBuffers(1, &massIndexBuffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, massIndexBuffer);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, Mass.indexBufferSize(), Mass.indices, GL_STATIC_DRAW);
//======= Shaders ======//
std::string shaderDir = generated::ShaderPaths::getShaderDirectory();
std::vector<ShaderInfo> springShaders
{
ShaderInfo{ GL_VERTEX_SHADER, shaderDir + "Spring.vs.glsl" },
ShaderInfo{ GL_FRAGMENT_SHADER, shaderDir + "Spring.fs.glsl" }
};
mShaders.push_back(ShaderPointer(new Shader));
mShaders[0]->compileShaders(springShaders);
mShaders[0]->linkShaders();
//===== Clean ups to prevent memory leaks =====//
Spring.cleanup();
Mass.cleanup();
}
Spring::~Spring()
{
glDeleteVertexArrays(1, &mVertexArrayObject);
glDeleteBuffers(1, &mSpringBuffer);
}
void Spring::renderGeometry(atlas::math::Matrix4 projection, atlas::math::Matrix4 view) {
// To avoid warnings from unused variables, you can use the
//UNUSED macro.
UNUSED(projection);
UNUSED(view);
mShaders[0]->enableShaders();
glBindVertexArray(mVertexArrayObject);
GLint dominatingColorUniformLocation = mShaders[0]->getUniformVariable("dominatingColor");
//========== Draw Spring ===============//
glm::vec3 springColor(0.0f, 1.0f, 0.0f);
glUniform3fv(dominatingColorUniformLocation, 1, &springColor[0]); //Send the location of the first float
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, springIndexBufferID);
glDrawElements(GL_LINES, numSpringIndices, GL_UNSIGNED_SHORT, 0);
//======================================//
//========= Draw Mass =================//
glm::vec3 massColor(1.0f, 0.0f, 0.0f);
glUniform3fv(dominatingColorUniformLocation, 1, &massColor[0]); //Send the location of the first float
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, massIndexBuffer);
glDrawElements(GL_TRIANGLES, numMassIndices, GL_UNSIGNED_SHORT, 0);
//======================================//
mShaders[0]->disableShaders();
}
void Spring::updateGeometry(atlas::utils::Time const& t) {
mModel = glm::translate(Matrix4(1.0f), mPosition);
}
glm::vec3 Spring::calculateConnectionPoint(glm::vec3 anchorPosition) {
glm::vec3 temp = glm::vec3(anchorPosition.x, anchorPosition.y - (18 * d), 0.0f);
return temp;
}
的ObjectGenerator类看起来像这样任何好奇
#include "ObjectGenerator.h"
#define NUM_ARRAY_ELEMENTS(a) sizeof(a)/sizeof(*a);
ShapeData ObjectGenerator::makeSpring(glm::vec3 anchorPosition, GLfloat stretch, GLfloat d) {
ShapeData ret;
static const Vertex vertices[] = {
glm::vec3(anchorPosition.x, anchorPosition.y, 0.0f), // 0
glm::vec3(1.0f, 0.0f, 0.0f), // Spring Color
glm::vec3(anchorPosition.x, anchorPosition.y - d,0.0f), // 1
glm::vec3(1.0f, 0.0f, 0.0f), // Spring Color
glm::vec3(anchorPosition.x + stretch, anchorPosition.y - (2 * d), 0.0f), // 2
glm::vec3(1.0f, 0.0f, 0.0f), // Spring Color
glm::vec3(anchorPosition.x - stretch, anchorPosition.y - (4 * d), 0.0f), // 3
glm::vec3(1.0f, 0.0f, 0.0f), // Spring Color
glm::vec3(anchorPosition.x + stretch, anchorPosition.y - (6 * d), 0.0f), // 4
glm::vec3(1.0f, 0.0f, 0.0f), // Spring Color
glm::vec3(anchorPosition.x - stretch, anchorPosition.y - (8 * d), 0.0f), // 5
glm::vec3(1.0f, 0.0f, 0.0f), // Spring Color
glm::vec3(anchorPosition.x + stretch, anchorPosition.y - (10 * d), 0.0f), // 6
glm::vec3(1.0f, 0.0f, 0.0f), // Spring Color
glm::vec3(anchorPosition.x - stretch, anchorPosition.y - (12 * d), 0.0f), // 7
glm::vec3(1.0f, 0.0f, 0.0f), // Spring Color
glm::vec3(anchorPosition.x + stretch, anchorPosition.y - (14 * d), 0.0f), // 8
glm::vec3(1.0f, 0.0f, 0.0f), // Spring Color
glm::vec3(anchorPosition.x - stretch, anchorPosition.y - (16 * d), 0.0f), // 9
glm::vec3(1.0f, 0.0f, 0.0f), // Spring Color
glm::vec3(anchorPosition.x, anchorPosition.y - (17 * d), 0.0f), // 10
glm::vec3(1.0f, 0.0f, 0.0f), // Spring Color
glm::vec3(anchorPosition.x, anchorPosition.y - (18 * d), 0.0f), // 11
glm::vec3(1.0f, 0.0f, 0.0f), // Spring Color
};
ret.numVertices = NUM_ARRAY_ELEMENTS(vertices);
ret.vertices = new Vertex[ret.numVertices];
memcpy(ret.vertices, vertices, sizeof(vertices)); //memcpy(dest, source, size);
GLushort indices[] = { 0,1 ,1,2, 2,3, 3,4, 4,5, 5,6, 6,7, 7,8, 8,9, 9,10, 10,11 };
ret.numIndices = NUM_ARRAY_ELEMENTS(indices);
ret.indices = new GLushort[ret.numIndices];
memcpy(ret.indices, indices, sizeof(indices));
return ret;
}
ShapeData ObjectGenerator::makeMass(glm::vec3 connectionPoint, GLfloat width, GLfloat height) {
ShapeData ret;
static const Vertex vertices[] = {
//=================Mass==============//
glm::vec3(connectionPoint.x - width, connectionPoint.y, 0.0f), //top Left 0
glm::vec3(0.0f, 1.0f, 0.0f), // Mass Color
glm::vec3(connectionPoint.x + width, connectionPoint.y, 0.0f), //top Right 1
glm::vec3(0.0f, 1.0f, 0.0f), // Mass Color
glm::vec3(connectionPoint.x + width, connectionPoint.y - height, 0.0f), // bottom right 2
glm::vec3(0.0f, 1.0f, 0.0f), // Mass Color
glm::vec3(connectionPoint.x - width, connectionPoint.y - height, 0.0f), // bottom left 3
glm::vec3(0.0f, 1.0f, 0.0f), // Mass Color
};
ret.numVertices = NUM_ARRAY_ELEMENTS(vertices);
ret.vertices = new Vertex[ret.numVertices];
memcpy(ret.vertices, vertices, sizeof(vertices)); //memcpy(dest, source, size);
GLushort indices[] = {0,1,3, 1,2,3 };
ret.numIndices = NUM_ARRAY_ELEMENTS(indices);
ret.indices = new GLushort[ret.numIndices];
memcpy(ret.indices, indices, sizeof(indices));
return ret;
}
您是否使用核心OpenGL配置文件？ –
你是什么意思，当你一起画画时？ – immibis
如果你看我的renderGeometry，我试图绘制弹簧和质量（质量只是一个矩形）。现在，由注释“Draw Spring”和“Draw Mass”强调的部分未被注释，以及构造函数中相应的缓冲区初始化器。这意味着这两个对象正在绘制。如果我注释掉renderGeometry方法中的“Draw Spring”部分和构造函数中的“Spring Buffer”部分，则只会绘制出按预期工作的质量。同样的，当我做相反的事情时，春天会像预期的那样呈现。 – nhoughto