SyndicatQuebecoisdelaConstr.../SQCSim2021/vertexbuffer.cpp
2021-10-11 11:37:58 -04:00

77 lines
2.4 KiB
C++

#include "vertexbuffer.h"
#include <cassert>
#include <climits>
VertexBuffer::VertexBuffer() : m_isValid(false) {
}
VertexBuffer::~VertexBuffer() {
if(m_isValid) {
glDeleteBuffers(1, &m_vertexVboId);
glDeleteBuffers(1, &m_indexVboId);
}
}
bool VertexBuffer::IsValid() const {
return m_isValid;
}
void VertexBuffer::SetMeshData(VertexData* vd, int vertexCount) {
assert(vertexCount <= USHRT_MAX);
if(vertexCount == 0)
return;
if(!m_isValid) {
glGenBuffers(1, &m_vertexVboId);
glGenBuffers(1, &m_indexVboId);
}
m_vertexCount = vertexCount;
glBindBuffer(GL_ARRAY_BUFFER, m_vertexVboId);
glBufferData(GL_ARRAY_BUFFER, sizeof(VertexData) * vertexCount, vd, GL_STATIC_DRAW);
// Pour le moment, generer le index array pour inclure tout les vertex, sans
// optimisation pour reduire le nombre de vertex envoyes a la carte
// Idealement cet array devrait etre utiliser pour reutiliser les vertex et ainsi
// sauver du temps en envoyant moins de donnees a la carte (il devrait etre construit
// en meme temps que le buffer vd est rempli..)
uint16_t* idx = new uint16_t[vertexCount];
for(int i = 0; i < vertexCount; ++i)
idx[i] = i;
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_indexVboId);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(uint16_t) * vertexCount, idx, GL_STATIC_DRAW);
delete [] idx;
m_isValid = true;
}
void VertexBuffer::Render() const {
if(IsValid())
{
glClientActiveTexture(GL_TEXTURE0);
glBindBuffer(GL_ARRAY_BUFFER, m_vertexVboId);
glEnableClientState(GL_VERTEX_ARRAY);
glVertexPointer(3, GL_FLOAT, sizeof(VertexData), (char*)0);
glEnableClientState(GL_COLOR_ARRAY);
glColorPointer(3, GL_FLOAT, sizeof(VertexData), (char*)12);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);
glTexCoordPointer(2, GL_FLOAT, sizeof(VertexData), (char*)24);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_indexVboId);
glDrawElements(GL_QUADS, m_vertexCount, GL_UNSIGNED_SHORT, (char*)0);
// TODO
//glDrawRangeElements(GL_TRIANGLES, 0, 3, 3, GL_UNSIGNED_SHORT, (char*)0);
glDisableClientState(GL_VERTEX_ARRAY);
glDisableClientState(GL_COLOR_ARRAY);
glDisableClientState(GL_TEXTURE_COORD_ARRAY);
}
}
int VertexBuffer::Count() const {
return m_vertexCount;
}