Initial commit.

texture.cpp

@@ -0,0 +1,99 @@
+// -*- C++ -*-
+
+#include <OpenGL/gl.h>
+#include <OpenGL/glu.h>
+#include <SDL/sdl.h>
+#include <SDL_image/SDL_image.h>
+#include <iostream>
+#include <string>
+#include <vector>
+
+#include "resource.h"
+#include "texture.h"
+
+using namespace mbostock;
+
+class TextureImpl : public Texture {
+public:
+  TextureImpl(const char* path);
+  virtual ~TextureImpl();
+
+  void initialize();
+  virtual void bind() const;
+
+private:
+  GLuint id_;
+  bool alpha_;
+  const std::string path_;
+};
+
+TextureImpl::TextureImpl(const char* path)
+    : id_(GL_NONE), alpha_(false), path_(path) {
+}
+
+TextureImpl::~TextureImpl() {
+  if (id_ != GL_NONE) {
+    glDeleteTextures(1, &id_);
+  }
+}
+
+void TextureImpl::initialize() {
+  if (id_ != GL_NONE) {
+    glDeleteTextures(1, &id_);
+  }
+
+  std::string path(Resources::path());
+  path.append(path_);
+  SDL_Surface* image = IMG_Load(path.c_str());
+  if (image == NULL) {
+    std::cerr << "Couldn't load " << path << ": " << SDL_GetError() << "\n";
+    id_ = GL_NONE;
+    return;
+  }
+
+	glGenTextures(1, &id_);
+	glBindTexture(GL_TEXTURE_2D, id_);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+  alpha_ = (image->format->BytesPerPixel == 4);
+  GLenum byteOrder = alpha_
+          ? ((image->format->Rmask == 0x000000FF) ? GL_RGBA : GL_BGRA)
+          : ((image->format->Rmask == 0x000000FF) ? GL_RGB : GL_BGR);
+
+	glTexImage2D(GL_TEXTURE_2D, 0,
+      image->format->BytesPerPixel, image->w, image->h, 0,
+      byteOrder, GL_UNSIGNED_BYTE, image->pixels);
+
+  gluBuild2DMipmaps(GL_TEXTURE_2D,
+      image->format->BytesPerPixel, image->w, image->h,
+      byteOrder, GL_UNSIGNED_BYTE, image->pixels);
+
+  SDL_FreeSurface(image);
+}
+
+void TextureImpl::bind() const {
+  if (alpha_) {
+    glEnable(GL_BLEND);
+    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+  }
+  glBindTexture(GL_TEXTURE_2D, id_);
+}
+
+static std::vector<TextureImpl*>& textures() {
+  static std::vector<TextureImpl*> v;
+  return v;
+}
+
+const Texture& Textures::fromFile(const char* path) {
+  TextureImpl* texture = new TextureImpl(path);
+  textures().push_back(texture);
+  return *texture;
+}
+
+void Textures::initialize() {
+  std::vector<TextureImpl*>::const_iterator i;
+  for (i = textures().begin(); i != textures().end(); i++) {
+    (*i)->initialize();
+  }
+}