125 lines
3.2 KiB
C++

#pragma once
#include "MeshData.hpp"
#include "gl_util.hpp"
inline constexpr size_t calc_size(const VertexAttribute attrs[]) {
size_t vertexSize = 0;
for (int i = 0; attrs[i].count; i++) {
vertexSize += attrs[i].size();
}
return vertexSize;
}
template <typename VertexStructure>
Mesh<VertexStructure>::Mesh(const MeshData<VertexStructure>& data)
: Mesh(
data.vertices.data(),
data.vertices.size(),
data.indices.data(),
data.indices.size()
) {
}
template <typename VertexStructure>
Mesh<VertexStructure>::Mesh(
const VertexStructure* vertexBuffer,
size_t vertices,
const uint32_t* indexBuffer,
size_t indices
)
: vao(0), vbo(0), ibo(0), vertexCount(0), indexCount(0) {
static_assert(
calc_size(VertexStructure::ATTRIBUTES) == sizeof(VertexStructure)
);
const auto& attrs = VertexStructure::ATTRIBUTES;
MeshStats::meshesCount++;
glGenVertexArrays(1, &vao);
glGenBuffers(1, &vbo);
reload(vertexBuffer, vertices, indexBuffer, indices);
// attributes
int offset = 0;
for (int i = 0; attrs[i].count; i++) {
const VertexAttribute& attr = attrs[i];
glVertexAttribPointer(
i,
attr.count,
gl::to_glenum(attr.type),
attr.normalized,
sizeof(VertexStructure),
(GLvoid*)(size_t)offset
);
glEnableVertexAttribArray(i);
offset += attr.size();
}
glBindVertexArray(0);
}
template <typename VertexStructure>
Mesh<VertexStructure>::~Mesh() {
MeshStats::meshesCount--;
glDeleteVertexArrays(1, &vao);
glDeleteBuffers(1, &vbo);
if (ibo != 0) {
glDeleteBuffers(1, &ibo);
}
}
template <typename VertexStructure>
void Mesh<VertexStructure>::reload(
const VertexStructure* vertexBuffer,
size_t vertexCount,
const uint32_t* indexBuffer,
size_t indexCount
) {
this->vertexCount = vertexCount;
this->indexCount = indexCount;
glBindVertexArray(vao);
glBindBuffer(GL_ARRAY_BUFFER, vbo);
if (vertexBuffer != nullptr && vertexCount != 0) {
glBufferData(
GL_ARRAY_BUFFER,
vertexCount * sizeof(VertexStructure),
vertexBuffer,
GL_STREAM_DRAW
);
} else {
glBufferData(GL_ARRAY_BUFFER, 0, {}, GL_STREAM_DRAW);
}
if (indexBuffer != nullptr && indexCount != 0) {
if (ibo == 0) glGenBuffers(1, &ibo);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ibo);
glBufferData(
GL_ELEMENT_ARRAY_BUFFER,
sizeof(uint32_t) * indexCount,
indexBuffer,
GL_STATIC_DRAW
);
} else if (ibo != 0) {
glDeleteBuffers(1, &ibo);
}
}
template <typename VertexStructure>
void Mesh<VertexStructure>::draw(unsigned int primitive) const {
MeshStats::drawCalls++;
glBindVertexArray(vao);
if (ibo != 0) {
glDrawElements(primitive, indexCount, GL_UNSIGNED_INT, nullptr);
} else {
glDrawArrays(primitive, 0, vertexCount);
}
glBindVertexArray(0);
}
template <typename VertexStructure>
void Mesh<VertexStructure>::draw() const {
draw(GL_TRIANGLES);
}