skein/src/orbitvisualizer.cpp

56 lines
1.4 KiB
C++

#include "orbitvisualizer.hpp"
#include "gfx.hpp"
OrbitVisualizer::OrbitVisualizer(const Orbit& orbit, const GLuint shaderProgram)
: _orbit(orbit), _shaderProgram(shaderProgram)
{
glGenVertexArrays(1, &_vao);
glGenBuffers(1, &_vbo);
}
void OrbitVisualizer::render(const float time)
{
regenerateVertices();
glUseProgram(_shaderProgram);
updateModelViewProjectionMatrix(_shaderProgram, time);
glBindVertexArray(_vao);
glBindBuffer(GL_ARRAY_BUFFER, _vbo);
glDrawArrays(GL_LINE_LOOP, 0, _vertices.size() / 3);
}
void OrbitVisualizer::regenerateVertices()
{
_vertices.clear();
for (int i = 0; i < _vertexCount; i++)
{
float t = (float)i / (float)_vertexCount * 2.0 * _pi;
glm::vec3 pos = _orbit.getPosition(t);
_vertices.push_back(pos.x);
_vertices.push_back(pos.y);
_vertices.push_back(pos.z);
}
glBindVertexArray(_vao);
glBindBuffer(GL_ARRAY_BUFFER, _vbo);
size_t vboBufferSize = _vertices.size() * sizeof(float);
glBufferData(GL_ARRAY_BUFFER, vboBufferSize, &_vertices[0], GL_STATIC_DRAW);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void*)0);
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindVertexArray(0);
}
OrbitVisualizer::~OrbitVisualizer()
{
glDeleteVertexArrays(1, &_vao);
glDeleteBuffers(1, &_vbo);
}