add unmodified version of TinyRenderer, a 500 line software renderer with vertex and pixel shaders, texture mapping and Wavefront .obj support.

examples/TinyRenderer/model.cpp

@@ -0,0 +1,108 @@
+#include <iostream>
+#include <fstream>
+#include <sstream>
+#include "model.h"
+
+Model::Model(const char *filename) : verts_(), faces_(), norms_(), uv_(), diffusemap_(), normalmap_(), specularmap_() {
+    std::ifstream in;
+    in.open (filename, std::ifstream::in);
+    if (in.fail()) return;
+    std::string line;
+    while (!in.eof()) {
+        std::getline(in, line);
+        std::istringstream iss(line.c_str());
+        char trash;
+        if (!line.compare(0, 2, "v ")) {
+            iss >> trash;
+            Vec3f v;
+            for (int i=0;i<3;i++) iss >> v[i];
+            verts_.push_back(v);
+        } else if (!line.compare(0, 3, "vn ")) {
+            iss >> trash >> trash;
+            Vec3f n;
+            for (int i=0;i<3;i++) iss >> n[i];
+            norms_.push_back(n);
+        } else if (!line.compare(0, 3, "vt ")) {
+            iss >> trash >> trash;
+            Vec2f uv;
+            for (int i=0;i<2;i++) iss >> uv[i];
+            uv_.push_back(uv);
+        }  else if (!line.compare(0, 2, "f ")) {
+            std::vector<Vec3i> f;
+            Vec3i tmp;
+            iss >> trash;
+            while (iss >> tmp[0] >> trash >> tmp[1] >> trash >> tmp[2]) {
+                for (int i=0; i<3; i++) tmp[i]--; // in wavefront obj all indices start at 1, not zero
+                f.push_back(tmp);
+            }
+            faces_.push_back(f);
+        }
+    }
+    std::cerr << "# v# " << verts_.size() << " f# "  << faces_.size() << " vt# " << uv_.size() << " vn# " << norms_.size() << std::endl;
+    load_texture(filename, "_diffuse.tga", diffusemap_);
+    load_texture(filename, "_nm_tangent.tga",      normalmap_);
+    load_texture(filename, "_spec.tga",    specularmap_);
+}
+
+Model::~Model() {}
+
+int Model::nverts() {
+    return (int)verts_.size();
+}
+
+int Model::nfaces() {
+    return (int)faces_.size();
+}
+
+std::vector<int> Model::face(int idx) {
+    std::vector<int> face;
+    for (int i=0; i<(int)faces_[idx].size(); i++) face.push_back(faces_[idx][i][0]);
+    return face;
+}
+
+Vec3f Model::vert(int i) {
+    return verts_[i];
+}
+
+Vec3f Model::vert(int iface, int nthvert) {
+    return verts_[faces_[iface][nthvert][0]];
+}
+
+void Model::load_texture(std::string filename, const char *suffix, TGAImage &img) {
+    std::string texfile(filename);
+    size_t dot = texfile.find_last_of(".");
+    if (dot!=std::string::npos) {
+        texfile = texfile.substr(0,dot) + std::string(suffix);
+        std::cerr << "texture file " << texfile << " loading " << (img.read_tga_file(texfile.c_str()) ? "ok" : "failed") << std::endl;
+        img.flip_vertically();
+    }
+}
+
+TGAColor Model::diffuse(Vec2f uvf) {
+    Vec2i uv(uvf[0]*diffusemap_.get_width(), uvf[1]*diffusemap_.get_height());
+    return diffusemap_.get(uv[0], uv[1]);
+}
+
+Vec3f Model::normal(Vec2f uvf) {
+    Vec2i uv(uvf[0]*normalmap_.get_width(), uvf[1]*normalmap_.get_height());
+    TGAColor c = normalmap_.get(uv[0], uv[1]);
+    Vec3f res;
+    for (int i=0; i<3; i++)
+        res[2-i] = (float)c[i]/255.f*2.f - 1.f;
+    return res;
+}
+
+Vec2f Model::uv(int iface, int nthvert) {
+    return uv_[faces_[iface][nthvert][1]];
+}
+
+float Model::specular(Vec2f uvf) {
+    Vec2i uv(uvf[0]*specularmap_.get_width(), uvf[1]*specularmap_.get_height());
+    return specularmap_.get(uv[0], uv[1])[0]/1.f;
+}
+
+Vec3f Model::normal(int iface, int nthvert) {
+    int idx = faces_[iface][nthvert][2];
+    return norms_[idx].normalize();
+}
+