games/learn-opengl
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Can now load a glb model with textures embedded in the model. Further cleanup coming.

Browse source
This commit is contained in:
Zed A. Shaw 2026-08-24 16:29:06 -04:00
parent 5b5e8a9fb0
commit c6a7c42a4e
12 changed files with 323 additions and 194 deletions
Download patch file Download diff file Expand all files Collapse all files

108
14-refactor/src/model.cpp
View file

@ -1,20 +1,14 @@
#include "model.hpp"
#include "dbc.hpp"
#include <print>
unsigned int TextureFromFile(const std::string& path, const std::string& directory, bool gamma)
{
std::string filename = path + "/" + filename;
unsigned int TextureFromFile(const std::string& path, const std::string& directory);
unsigned int TextureFromInternal(const aiScene *scene, size_t index);
unsigned int to_gl_texture(unsigned char *data, int width, int height, int nrComponents) {
unsigned int textureID;
glGenTextures(1, &textureID);
int width = 0;
int height = 0;
int nrComponents = 0;
unsigned char *data = stbi_load(filename.c_str(), &width, &height, &nrComponents, 0);
dbc::check(data != nullptr, $F("Failed to load texture {}", filename));
GLenum format = GL_RGB;
if (nrComponents == 1) {
@ -34,6 +28,48 @@ unsigned int TextureFromFile(const std::string& path, const std::string& directo
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
return textureID;
}
unsigned int TextureFromInternal(const aiScene *scene, size_t index) {
const aiTexture *aiTex = scene->mTextures[index];
unsigned int textureID = 0;
int width = 0;
int height = 0;
int nrComponents = 0;
unsigned char *data = nullptr;
const unsigned char* dataBytes = (const unsigned char*)aiTex->pcData;
if(aiTex->mHeight == 0) {
// compressed texture (PNG or JPG)
size_t dataSize = aiTex->mWidth;
data = stbi_load_from_memory(dataBytes, dataSize, &width, &height, &nrComponents, 0);
textureID = to_gl_texture(data, width, height, nrComponents);
stbi_image_free(data);
} else {
data = (unsigned char*)aiTex->pcData;
width = aiTex->mWidth;
height = aiTex->mHeight;
nrComponents = 4; // either BGRA8888 or RGBA8888
textureID = to_gl_texture(data, width, height, nrComponents);
}
return textureID;
}
unsigned int TextureFromFile(const std::string& path, const std::string& directory)
{
std::string filename = directory + "/" + path;
int width = 0;
int height = 0;
int nrComponents = 0;
unsigned char *data = stbi_load(filename.c_str(), &width, &height, &nrComponents, 0);
dbc::check(data != nullptr, $F("Failed to load texture {}", filename));
unsigned int textureID = to_gl_texture(data, width, height, nrComponents);
stbi_image_free(data);
return textureID;
@ -45,9 +81,14 @@ void Model::Draw(Shader &shader) {
}
}
void Model::loadModel(std::string path) {
void Model::loadModel(const std::string& path) {
Assimp::Importer importer;
const aiScene* scene = importer.ReadFile(path, aiProcess_Triangulate | aiProcess_GenSmoothNormals | aiProcess_FlipUVs | aiProcess_CalcTangentSpace);
const aiScene* scene = importer.ReadFile(path,
aiProcess_Triangulate |
aiProcess_GenSmoothNormals |
aiProcess_FlipUVs |
aiProcess_CalcTangentSpace);
dbc::check(scene != nullptr, "Assimp ReadFile return null");
dbc::check(!(scene->mFlags & AI_SCENE_FLAGS_INCOMPLETE), "Assimp says incomplete.");
@ -118,54 +159,53 @@ Mesh Model::processMesh(aiMesh *mesh, const aiScene *scene) {
// normal: texture_normalN
// 1. diffuse maps
std::vector<Texture> diffuseMaps = loadMaterialTextures(material, aiTextureType_DIFFUSE, "texture_diffuse");
textures.insert(textures.end(), diffuseMaps.begin(), diffuseMaps.end());
loadMaterialTextures(textures, scene, material, aiTextureType_DIFFUSE, "texture_diffuse");
// 2. specular maps
std::vector<Texture> specularMaps = loadMaterialTextures(material, aiTextureType_SPECULAR, "texture_specular");
textures.insert(textures.end(), specularMaps.begin(), specularMaps.end());
loadMaterialTextures(textures, scene, material, aiTextureType_SPECULAR, "texture_specular");
// 3. normal maps
std::vector<Texture> normalMaps = loadMaterialTextures(material, aiTextureType_HEIGHT, "texture_normal");
textures.insert(textures.end(), normalMaps.begin(), normalMaps.end());
loadMaterialTextures(textures, scene, material, aiTextureType_HEIGHT, "texture_normal");
// 4. height maps
std::vector<Texture> heightMaps = loadMaterialTextures(material, aiTextureType_AMBIENT, "texture_height");
textures.insert(textures.end(), heightMaps.begin(), heightMaps.end());
loadMaterialTextures(textures, scene, material, aiTextureType_AMBIENT, "texture_height");
return Mesh(vertices, indices, textures);
}
std::vector<Texture> Model::loadMaterialTextures(aiMaterial *mat, aiTextureType type, std::string typeName)
void Model::loadMaterialTextures(std::vector<Texture>& textures, const aiScene *scene, aiMaterial *mat, aiTextureType type, std::string typeName)
{
fmt::println("TEXTURE COUNT: {}, {}, {}", (int)type, typeName, mat->GetTextureCount(type));
std::vector<Texture> textures;
for(unsigned int i = 0; i < mat->GetTextureCount(type); i++) {
aiString str;
mat->GetTexture(type, i, &str);
std::string tx_str{str.C_Str()};
dbc::check(!tx_str.empty(), "Texture has empty path, should be impossible?");
bool skip = false;
for(unsigned int j = 0; j < textures_loaded.size(); j++) {
if(textures_loaded[j].path == tx_str) {
textures.push_back(textures_loaded[j]);
skip = true;
break;
if(textures_loaded.contains(tx_str)) {
textures.push_back(textures_loaded.at(tx_str));
} else {
unsigned int tx_id = 0;
// if it's a *# style path then it's internal
if(tx_str[0] == '*') {
// get the texture from the internal version
tx_id = TextureFromInternal(scene, std::stoi(tx_str.substr(1)));
} else {
// else get it from a file
tx_id = TextureFromFile(tx_str, directory);
}
}
if(!skip) {
Texture texture{
.id = TextureFromFile(tx_str, directory),
.id = tx_id,
.type = typeName,
.path = tx_str,
};
textures.push_back(texture);
textures_loaded.push_back(texture);
textures_loaded.try_emplace(tx_str, texture);
}
}
return textures;
}