1 files changed, 167 insertions, 537 deletions

diff --git a/source/main.cpp b/source/main.cpp
index a9e5c81..7deb893 100644
--- a/source/main.cpp
+++ b/source/main.cpp
@@ -2,14 +2,14 @@
 #include <stdlib.h>
 #include <SDL2/SDL.h>
 #include <glad/glad.h>
-#include <assimp/Importer.hpp>
-#include <assimp/scene.h>
-#include <assimp/postprocess.h>
 #include <vector>
 
 #define STB_IMAGE_IMPLEMENTATION
 #include "stb_image.h"
 
+#include <ft2build.h>
+#include FT_FREETYPE_H
+
 /* @lookup:
 *  - understand kernals, how they work and how they affect post processing
 *  - Check to see why it is necessary to do glBindTexture() 
@@ -50,6 +50,31 @@ typedef u8        b8;
 
 // =========== Shader Loading =============
 
+enum Texture_Filtering { TF_NEAREST, TF_LINEAR };
+
+struct GlTexturedQuad {
+  u32 vao;
+  u32 vbo;
+  u32 texture_id;
+};
+
+struct GlShader {
+  u32 id;
+  s32 model_loc;
+  s32 view_loc;
+  s32 proj_loc;
+};
+
+void gl_shader_load_locations(GlShader *shader)
+{
+  glUseProgram(shader->id);
+  shader->model_loc = glGetUniformLocation(shader->id, "Model");
+  shader->view_loc = glGetUniformLocation(shader->id, "View");
+  shader->proj_loc = glGetUniformLocation(shader->id, "Projection");
+
+  return;
+}
+
 unsigned int gl_create_vertex_shader(char* vertex_shader_source)
 {
 	unsigned int vertex_shader = glCreateShader(GL_VERTEX_SHADER);
@@ -121,36 +146,25 @@ unsigned int gl_shader_program(char* vertex_shader_source, char* fragment_shader
   return shader_program;
 }
 
-Mat4 camera_create4m(Vec3 camera_pos, Vec3 camera_look, Vec3 camera_up)
+u32 gl_shader_program_from_path(char* vs_path, char* fs_path)
 {
-	// @note: We do this because this allows the camera to have the axis it looks at
-	// inwards be the +z axis.
-	// If we did not do this, then the inward axis the camera looks at would be negative. 
-	// I am still learning from learnopengl.com but I imagine that this was done for conveniences' sake.
-	Vec3 camera_forward_dir = normalize3v(subtract3v(camera_pos, camera_look));
-	Vec3 camera_right_dir   = normalize3v(cross_multiply3v(camera_up, camera_forward_dir));
-	Vec3 camera_up_dir      = normalize3v(cross_multiply3v(camera_forward_dir, camera_right_dir));
-    
-	Mat4 res = lookat4m(camera_up_dir, camera_forward_dir, camera_right_dir, camera_pos);
-    
-	return res;
-}
+  // @todo: add failure handling here
+  // what to do if we fail to read the shaders
+  size_t read_count;
+  char* vs = (char*)SDL_LoadFile(vs_path, &read_count);
+  char* fs = (char*)SDL_LoadFile(fs_path, &read_count);
 
-Vec3 camera_look_around(r32 angle_pitch, r32 angle_yaw)
-{
-    Vec3 camera_look = {0.0};
-    camera_look.x = cosf(angle_yaw) * cosf(angle_pitch);
-    camera_look.y = sinf(angle_pitch);
-    camera_look.z = sinf(angle_yaw) * cosf(angle_pitch);
-    camera_look = normalize3v(camera_look);
-    
-    return camera_look;
+  u32 shader_program = gl_shader_program(vs, fs);
+
+  return shader_program;
 }
 
-s32 gl_load_texture(u32 texture_id, const char* path)
+s32 gl_load_texture(u32 texture_id, char *path, enum Texture_Filtering filter)
 {
   s32 width, height, nrChannels;
+  stbi_set_flip_vertically_on_load(1);
   unsigned char *data = stbi_load(path, &width, &height, &nrChannels, 0);
+  stbi_set_flip_vertically_on_load(0);
   if (data)
   {
     GLenum format;
@@ -167,431 +181,137 @@ s32 gl_load_texture(u32 texture_id, const char* path)
 
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-    stbi_image_free(data);
-  }
-  else
-  {
-    printf("failed to load image texture at path: %s", path);
-    stbi_image_free(data);
-  }
-
-  return texture_id;
-}
-
-// =================== Model Loading ========================
-// This section contains a whole host of things:
-// 1. classes
-// 2. std::vectors
-// 3. std::strings
-// that I have only used as a glue for I did not know if I had the model loading setup properly.
-// @todo: replace these things eventually. For now the goal is to complete learnopengl
-
-s32 TextureFromFile(const char* filepath, std::string directory)
-{
-  // @note: this function is stupid as it already became outdated as I needed to tweak the parameters
-  // for wrapping. Either those become function parameters (Which makes sense I guess) or I look at
-  // exactly what steps I am reusing and just make that a function so the function is called fewer times.
-  //
-  // I am guessing this won't look good from a design point of view for all those jobs and postings, even if
-  // this may be the simpler and faster thing to do, albeit at the cost of typing.
-  std::string filename = std::string(filepath);
-  filename = directory + '/' + filename;
-
-  u32 texid;
-  glGenTextures(1, &texid);
-
-  s32 width, height, nrChannels;
-  unsigned char *data = stbi_load(filename.c_str(), &width, &height, &nrChannels, 0);
-  if (data)
-  {
-    GLenum format;
-    if (nrChannels == 1)
-      format = GL_RED;
-    else if (nrChannels == 3)
-      format = GL_RGB;
-    else if (nrChannels == 4)
-      format = GL_RGBA;
-
-    glBindTexture(GL_TEXTURE_2D, texid);
-    glTexImage2D(GL_TEXTURE_2D, 0, format, width, height, 0, format, GL_UNSIGNED_BYTE, data);
-    glGenerateMipmap(GL_TEXTURE_2D);
-
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-
-    stbi_image_free(data);
-  }
-  else
-  {
-    printf("failed to load image texture at path: %s", filepath);
-    stbi_image_free(data);
-  }
-
-  return texid;
-}
-
-enum TextureType { TextureDiffuse=0, TextureSpecular };
 
-struct Vertex {
-  Vec3 position;
-  Vec3 normal;
-  Vec2 texture;
-};
-
-struct Texture {
-  u32 id;
-  enum TextureType type;
-  std::string fname;
-};
-
-class Mesh {
-  public:
-  std::vector<Vertex>  vertices;
-  std::vector<u32> indices;
-  std::vector<Texture> textures;
-
-  u32 vao;
-  u32 vbo;
-  u32 ebo;
-
-  Mesh(std::vector<Vertex> vertices, std::vector<u32> indices, std::vector<Texture> textures)
-  {
-    this->vertices = vertices;
-    this->indices = indices;
-    this->textures = textures;
-
-    // setup mesh shader stuff
-    glGenVertexArrays(1, &vao);
-    glGenBuffers(1, &vbo);
-    glGenBuffers(1, &ebo);
-
-    glBindVertexArray(vao);
-
-    glBindBuffer(GL_ARRAY_BUFFER, vbo);
-    glBufferData(GL_ARRAY_BUFFER, this->vertices.size() * sizeof(struct Vertex), &(this->vertices[0]), GL_STATIC_DRAW);
-
-    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ebo);
-    glBufferData(GL_ELEMENT_ARRAY_BUFFER, this->indices.size() * sizeof(u32), &(this->indices[0]), GL_STATIC_DRAW);
-
-    // position
-    glEnableVertexAttribArray(0);
-    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), (void*)0);
-    // normal
-    glEnableVertexAttribArray(1);
-    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), (void*)offsetof(Vertex, normal));
-    // texture
-    glEnableVertexAttribArray(2);
-    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex), (void*)offsetof(Vertex, texture));
-
-    glBindVertexArray(0);
-  }
-
-  void draw(u32 shader_program)
-  {
-    glUseProgram(shader_program);
+    u32 min_filter;
+    u32 max_filter;
 
-    u32 diffuse_num = 1;
-    u32 specular_num = 1;
-    char tex_unit_name[64];
-    // set shininess
-    s32 mat_shine_loc = glGetUniformLocation(shader_program, "material.shininess");
-    glUniform1f(mat_shine_loc, 32.0f);
-
-    for (u32 i=0; i<textures.size(); i++)
+    if (filter == TF_LINEAR)
     {
-      struct Texture curr_tex = textures[i];
-      if (curr_tex.type == TextureDiffuse)
-      {
-        sprintf(tex_unit_name, "material.diffuse[%i]", diffuse_num);
-      }
-      else if (curr_tex.type == TextureSpecular)
-      {
-        sprintf(tex_unit_name, "material.diffuse[%i]", specular_num);
-      }
-
-      glActiveTexture(GL_TEXTURE0 + i);
-      s32 tex_unit_loc = glGetUniformLocation(shader_program, tex_unit_name);
-      glUniform1i(tex_unit_loc, i);
-      glBindTexture(GL_TEXTURE_2D, curr_tex.id);
+      min_filter = GL_LINEAR_MIPMAP_LINEAR;
+      max_filter = GL_LINEAR;
     }
-    glActiveTexture(GL_TEXTURE0);
-
-    glBindVertexArray(vao);
-    glDrawElements(GL_TRIANGLES, indices.size(), GL_UNSIGNED_INT, 0);
-    glBindVertexArray(0);
-  }
-
-  void draw_instanced(u32 shader_program, u32 instance_count)
-  {
-    glUseProgram(shader_program);
-
-    u32 diffuse_num = 1;
-    u32 specular_num = 1;
-    char tex_unit_name[64];
-    // set shininess
-    s32 mat_shine_loc = glGetUniformLocation(shader_program, "material.shininess");
-    glUniform1f(mat_shine_loc, 32.0f);
-
-    for (u32 i=0; i<textures.size(); i++)
+    else if (filter == TF_NEAREST)
     {
-      struct Texture curr_tex = textures[i];
-      if (curr_tex.type == TextureDiffuse)
-      {
-        sprintf(tex_unit_name, "material.diffuse[%i]", diffuse_num);
-      }
-      else if (curr_tex.type == TextureSpecular)
-      {
-        sprintf(tex_unit_name, "material.diffuse[%i]", specular_num);
-      }
-
-      glActiveTexture(GL_TEXTURE0 + i);
-      s32 tex_unit_loc = glGetUniformLocation(shader_program, tex_unit_name);
-      glUniform1i(tex_unit_loc, i);
-      glBindTexture(GL_TEXTURE_2D, curr_tex.id);
+      min_filter = GL_NEAREST_MIPMAP_LINEAR;
+      max_filter = GL_NEAREST;
     }
-    glActiveTexture(GL_TEXTURE0);
 
-    glBindVertexArray(vao);
-    glDrawElementsInstanced(GL_TRIANGLES, indices.size(), GL_UNSIGNED_INT, 0, instance_count);
-    glBindVertexArray(0);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, min_filter);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, max_filter);
+    stbi_image_free(data);
   }
-};
-
-class Model
-{
-  public:
-    std::vector<Texture> loaded_textures;
-    std::vector<Mesh> meshes;
-    std::string directory;
-
-    Model(std::string path)
-    {
-      load_model(path);
-    }
-    void instance_mesh();
-    void draw(u32 shader_program);
-    void draw_instanced(u32 shader_program, u32 instance_count);
-  private:
-    void load_model(std::string path);
-    void process_node(aiNode *node, const aiScene *scene);
-    Mesh process_mesh(aiMesh *mesh, const aiScene *scene);
-    std::vector<Texture> load_material_textures(aiMaterial *mat, aiTextureType type, TextureType type_name);
-};
-
-void Model::instance_mesh()
-{
-  for (u32 i=0; i < meshes.size(); i++)
+  else
   {
-    Mesh curr_mesh = meshes[i];
-    glBindVertexArray(curr_mesh.vao);
-    glVertexAttribPointer(3, 4, GL_FLOAT, GL_FALSE, 16 * sizeof(u32), (void*)0);
-    glEnableVertexAttribArray(3);
-
-    glVertexAttribPointer(4, 4, GL_FLOAT, GL_FALSE, 16 * sizeof(u32), (void*)(4*sizeof(u32)));
-    glEnableVertexAttribArray(4);
-
-    glVertexAttribPointer(5, 4, GL_FLOAT, GL_FALSE, 16 * sizeof(u32), (void*)(8*sizeof(u32)));
-    glEnableVertexAttribArray(5);
-
-    glVertexAttribPointer(6, 4, GL_FLOAT, GL_FALSE, 16 * sizeof(u32), (void*)(12*sizeof(u32)));
-    glEnableVertexAttribArray(6);
-
-    glBindBuffer(GL_ARRAY_BUFFER, 0);
-    glVertexAttribDivisor(3, 1);
-    glVertexAttribDivisor(4, 1);
-    glVertexAttribDivisor(5, 1);
-    glVertexAttribDivisor(6, 1);
-
-    glBindVertexArray(0);
+    // @todo: logging
+    printf("failed to load image texture at path: %s", path);
+    stbi_image_free(data);
+    return -1; 
   }
+
+  return 0;
 }
 
-void Model::draw(u32 shader_program)
+GlTexturedQuad gl_setup_textured_quad(char* texture_path, enum Texture_Filtering filter)
 {
-  for (int i=0; i < meshes.size(); i++)
-  {
-    meshes[i].draw(shader_program);
-  }
+  // rendering is clock-wise
+  r32 quad_vertices[] = {
+    -1.0f, -1.0f,  0.0f,  0.0f, 0.0f, // bottom-left
+     1.0f, -1.0f,  0.0f,  1.0f, 0.0f, // bottom-right
+     1.0f,  1.0f,  0.0f,  1.0f, 1.0f, // top-right
+     1.0f,  1.0f,  0.0f,  1.0f, 1.0f, // top-right
+    -1.0f,  1.0f,  0.0f,  0.0f, 1.0f, // top-left
+    -1.0f, -1.0f,  0.0f,  0.0f, 0.0f, // bottom-left
+  };
+  u32 vao, vbo, tex_id;
+	glGenVertexArrays(1, &vao);
+	glGenBuffers(1, &vbo);
+
+	glBindVertexArray(vao);
+  glBindBuffer(GL_ARRAY_BUFFER, vbo);
+  glBufferData(GL_ARRAY_BUFFER, sizeof(quad_vertices), &quad_vertices, GL_STATIC_DRAW);
+  glEnableVertexAttribArray(0);
+  glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(r32), (void*)0);
+  glEnableVertexAttribArray(1);
+  glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(r32), (void*)(3*sizeof(r32)));
+  glBindVertexArray(0);
+
+  glGenTextures(1, &tex_id);
+  glActiveTexture(GL_TEXTURE0);
+  gl_load_texture(tex_id, texture_path, filter);
+
+  GlTexturedQuad tex_quad;
+  tex_quad.vao = vao;
+  tex_quad.vbo = vbo;
+  tex_quad.texture_id = tex_id;
+
+  return tex_quad;
 }
 
-void Model::draw_instanced(u32 shader_program, u32 instance_count)
+void gl_draw_tex_quad(u32 shader_program, GlTexturedQuad tex_quad)
 {
-  for (int i=0; i < meshes.size(); i++)
-  {
-    meshes[i].draw_instanced(shader_program, instance_count);
-  }
+  glUseProgram(shader_program);
+  s32 tex_id_loc = glGetUniformLocation(shader_program, "Texture");
+  glUniform1i(tex_id_loc, 0);
+  glBindVertexArray(tex_quad.vao);
+  glBindTexture(GL_TEXTURE_2D, tex_quad.texture_id);
+  glDrawArrays(GL_TRIANGLES, 0, 6);
 }
 
-void Model::load_model(std::string path)
+// =============== CAMERA STUFF =================
+// @note: Be sure to update and refactor the camera
+Mat4 camera_create4m(Vec3 camera_pos, Vec3 camera_look, Vec3 camera_up)
 {
-  Assimp::Importer import;
-  const aiScene *scene = import.ReadFile(path, aiProcess_Triangulate | aiProcess_FlipUVs);
-
-  if (!scene || scene->mFlags & AI_SCENE_FLAGS_INCOMPLETE || !scene->mRootNode)
-  {
-    printf("error loading model :%s\n", import.GetErrorString());
-    return;
-  }
-
-  directory = path.substr(0, path.find_last_of('/'));
-  process_node(scene->mRootNode, scene);
+	// @note: We do this because this allows the camera to have the axis it looks at
+	// inwards be the +z axis.
+	// If we did not do this, then the inward axis the camera looks at would be negative. 
+	// I am still learning from learnopengl.com but I imagine that this was done for conveniences' sake.
+	Vec3 camera_forward_dir = normalize3v(subtract3v(camera_pos, camera_look));
+	Vec3 camera_right_dir   = normalize3v(cross_multiply3v(camera_up, camera_forward_dir));
+	Vec3 camera_up_dir      = normalize3v(cross_multiply3v(camera_forward_dir, camera_right_dir));
+    
+	Mat4 res = lookat4m(camera_up_dir, camera_forward_dir, camera_right_dir, camera_pos);
+    
+	return res;
 }
 
-void Model::process_node(aiNode *node, const aiScene *scene)
+Vec3 camera_look_around(r32 angle_pitch, r32 angle_yaw)
 {
-  for (int i=0; i < node->mNumMeshes; i++)
-  {
-    aiMesh *mesh = scene->mMeshes[node->mMeshes[i]];
-    meshes.push_back(process_mesh(mesh, scene));
-  }
-
-  for (int i=0; i<node->mNumChildren; i++)
-  {
-    process_node(node->mChildren[i], scene);
-  }
+    Vec3 camera_look = {0.0};
+    camera_look.x = cosf(angle_yaw) * cosf(angle_pitch);
+    camera_look.y = sinf(angle_pitch);
+    camera_look.z = sinf(angle_yaw) * cosf(angle_pitch);
+    camera_look = normalize3v(camera_look);
+    
+    return camera_look;
 }
 
-Mesh Model::process_mesh(aiMesh *mesh, const aiScene *scene)
+int main(int argc, char* argv[])
 {
-  std::vector<Vertex> vertices;
-  std::vector<u32> indices;
-  std::vector<Texture> textures;
-
-  for (u32 i=0; i < mesh->mNumVertices; i++)
-  {
-    Vec3 position;
-    position.x = mesh->mVertices[i].x;
-    position.y = mesh->mVertices[i].y;
-    position.z = mesh->mVertices[i].z;
-
-    Vec3 normal;
-    normal.x = mesh->mNormals[i].x;
-    normal.y = mesh->mNormals[i].y;
-    normal.z = mesh->mNormals[i].z;
-
-    Vec2 texture = {0, 0};
-    if (mesh->mTextureCoords[0])
-    {
-      texture.x = mesh->mTextureCoords[0][i].x;
-      texture.y = mesh->mTextureCoords[0][i].y;
-    }
 
-    struct Vertex vertex;
-    vertex.position = position;
-    vertex.normal = normal;
-    vertex.texture = texture;
+  // Load freetype
+  FT_Library library;
+  FT_Face face;
 
-    vertices.push_back(vertex);
-  }
-  // process indices
-  for (u32 i = 0; i < mesh->mNumFaces; i++)
+  if (FT_Init_FreeType(&library))
   {
-    aiFace face = mesh->mFaces[i];
-    for(u32 j = 0; j < face.mNumIndices; j++)
-    {
-      indices.push_back(face.mIndices[j]);
-    }
+    printf("Error: Could not init freetype library\n");
+    return -1;
   }
-  // process material
-  if (mesh->mMaterialIndex >= 0)
+
+  FT_Error error = FT_New_Face(library, "assets/fonts/Arial.ttf", 0, &face);
+  if (error == FT_Err_Unknown_File_Format) 
   {
-    aiMaterial *material = scene->mMaterials[mesh->mMaterialIndex];
-    std::vector<Texture> diffuse_maps = load_material_textures(material, aiTextureType_DIFFUSE, TextureDiffuse);
-    textures.insert(textures.end(), diffuse_maps.begin(), diffuse_maps.end());
-    std::vector<Texture> specular_maps = load_material_textures(material, aiTextureType_SPECULAR, TextureSpecular);
-    textures.insert(textures.end(), specular_maps.begin(), specular_maps.end());
+    printf("Error: Font Loading Failed. The font format is unsupported.\n");
+    return -1;
   }
-
-  return Mesh(vertices, indices, textures);
-}
-
-std::vector<Texture> Model::load_material_textures(aiMaterial *mat, aiTextureType type, TextureType tex_type)
-{
-  std::vector<Texture> textures;
-  for(u32 i=0; i<mat->GetTextureCount(type); i++)
+  else if (error)
   {
-    bool load_texture = true;
-    aiString str;
-    mat->GetTexture(type, i, &str);
-    const char* fname = str.C_Str();
-
-    for (s32 j=0; j<loaded_textures.size();  j++)
-    {
-      if (std::strcmp(loaded_textures[j].fname.data(), fname) == 0)
-      {
-        load_texture = false;
-        textures.push_back(loaded_textures[j]);
-        break;
-      }
-    }
-    if (load_texture)
-    {
-      Texture texture;
-      texture.id = TextureFromFile(fname, directory);
-      texture.type = tex_type;
-      texture.fname = std::string(fname);
-      textures.push_back(texture);
-      loaded_textures.push_back(texture);
-    }
+    printf("Error: Font Loading Failed. Unknown error code: %d\n", error);
+    return -1;
   }
 
-  return textures;
-}
-
-class Shader {
-  // @note: this is a draft, I think frankly, it's a stupid idea to be making this at this point
-  // but my goal is to look at my code at this stage (which is in the second half of (or so I think)
-  // learnopengl and identify repeated code that I think I can yank out and can make convenient to write.
-  // The precondition for all of this is that I do not remodel the program based off of some vague idea of
-  // cleanliness in my head. This is all still very procedural, I just want to minimize the amount I type
-  // and at the same time see how well I can identify good abstractions
-  //
-  //
-  // I much prefer to have things be not a class, especially if I look at how I did my lovely
-  // math functions, which are so simple and straightforward
-  public:
-    u32 id;
-    
-    // @note: all well and good until you get compute shaders
-    // then the entire thing shits the bed
-    Shader(char* vertex_shader_source, char* fragment_shader_source) {
-      id = gl_shader_program(vertex_shader_source, fragment_shader_source);
-    }
+  FT_Set_Pixel_Sizes(face, 0, 48);
 
-    void use() {
-      glUseProgram(id);
-    }
-
-    void draw_triangles(u32 vao, u32 count) {
-      glBindVertexArray(vao);
-      glDrawArrays(GL_TRIANGLES, 0, count);
-    }
-
-    void set_1i(char* variable, s32 value) {
-      s32 loc = glGetUniformLocation(id, variable);
-      glUniform1i(loc, value);
-    }
-
-    void set_matrix4fv(char* variable, Mat4 value, int count) {
-      s32 loc = glGetUniformLocation(id, variable);
-      glUniformMatrix4fv(loc, count, GL_TRUE, value.buffer);
-    };
-
-    ~Shader() {
-      // @note: this can literally be replaced by another function that goes over the entire list
-      // of shader_programs near the program exit and deletes them, if I even need to do that.
-      glDeleteProgram(id);
-    }
-};
-
-int main(int argc, char* argv[])
-{
-
-  // ============ END ============
 	int width = 1024;
 	int height = 768;
     
@@ -615,7 +335,7 @@ int main(int argc, char* argv[])
                                           height,
                                           SDL_WINDOW_OPENGL);
     
-    SDL_SetRelativeMouseMode(SDL_TRUE);
+  SDL_SetRelativeMouseMode(SDL_TRUE);
    
 	// create an opengl context
 	SDL_GLContext context = SDL_GL_CreateContext(window);
@@ -637,91 +357,13 @@ int main(int argc, char* argv[])
     
   // filesystem playground stuff
   size_t read_count;
-  char* vertex_source = (char*)SDL_LoadFile("./source/shaders/model.vs.glsl", &read_count);
-  char* inst_vertex_source = (char*)SDL_LoadFile("./source/shaders/instanced_model.vs.glsl", &read_count);
-  char* fragment_source = (char*)SDL_LoadFile("./source/shaders/model.fs.glsl", &read_count);
-    
-  u32 shader_program = gl_shader_program(vertex_source, fragment_source);
-  u32 inst_shader_program = gl_shader_program(inst_vertex_source, fragment_source);
-    
-  stbi_set_flip_vertically_on_load(1);
+  GlShader tex_quad_shader;
+  tex_quad_shader.id = gl_shader_program_from_path("./source/shaders/textured_quad.vs.glsl", "./source/shaders/textured_quad.fs.glsl");
+  gl_shader_load_locations(&tex_quad_shader);
 
-  Model planet_model = Model(std::string("./assets/planet/planet.obj"));
-  Model rock_model = Model(std::string("assets/rock/rock.obj"));
+  GlTexturedQuad tex_quad1 = gl_setup_textured_quad("./assets/smiling.png", TF_LINEAR);
+  GlTexturedQuad tex_quad2 = gl_setup_textured_quad("./assets/container.jpg", TF_LINEAR);
   
-  float inst_vertices[] = {
-      // positions          // texture Coords (note we set these higher than 1 (together with GL_REPEAT as texture wrapping mode). this will cause the floor texture to repeat)
-      // BottomFace
-      -0.5f, -1.0f, -0.5f, // top-right
-       0.5f, -1.0f, -0.5f, // top-left
-       0.5f, -1.0f,  0.5f, // bottom-left
-       0.5f, -1.0f,  0.5f, // bottom-left
-      -0.5f, -1.0f,  0.5f, // bottom-right
-      -0.5f, -1.0f, -0.5f, // top-right
-      // Top face
-      -0.5f, -0.9f, -0.5f, // top-left
-       0.5f, -0.9f,  0.5f, // bottom-right
-       0.5f, -0.9f, -0.5f, // top-right     
-       0.5f, -0.9f,  0.5f, // bottom-right
-      -0.5f, -0.9f, -0.5f, // top-left
-      -0.5f, -0.9f,  0.5f // bottom-left     
-  };
-  const u32 instance_count = 100000;
-  Mat4 *offsets = (Mat4 *)calloc(instance_count, sizeof(Mat4));
-  u32 amount = instance_count;
-  r32 offset = 7.0f;
-  r32 radius = 50.0f;
-  srand(SDL_GetTicks64());
-  for (u32 i = 0; i < amount; i++)
-  {
-    Mat4 model = init_value4m(1.0f);
-    
-    // 1. translation
-    u32 angle = (i*360)/amount;
-    r32 displacement = (rand()%(u32)(2 * offset * 100)) / 100.0f - offset;
-    r32 x = sin(angle) * radius + displacement; 
-    displacement = (rand()%(u32)(2 * offset * 100)) / 100.0f - offset;
-    r32 y = displacement * 1.5f;
-    displacement = (rand()%(u32)(2 * offset * 100)) / 100.0f - offset;
-    r32 z = cos(angle) * radius + displacement;
-    Mat4 translation = translation_matrix4m(x, y, z);
-
-    // 2. scale
-    r32 rnd_scale = (rand()%20) / 100.0f + 0.05;
-    Mat4 scale = scaling_matrix4m(rnd_scale, rnd_scale, rnd_scale);
-
-    // 3. rotation
-    r32 rot_angle = To_Radian(rand()%360);
-    Mat4 rotation = rotation_matrix4m(rot_angle, Vec3{0.4f, 0.6f, 0.8f});
-
-    model = multiply4m(rotation, model);
-    model = multiply4m(scale, model);
-    model = multiply4m(translation, model);
-
-    offsets[i] = to_col_major4m(model);
-  }
-    
-	u32 instance_vbo;
-  glGenBuffers(1, &instance_vbo);
-  glBindBuffer(GL_ARRAY_BUFFER, instance_vbo);
-
-#if 0
-  u32 offset_sz = offsets.size();
-  Mat4 *offset_ptr = offsets.data();
-#endif
-  u32 offset_sz = instance_count * sizeof(Mat4);
-  Mat4 *offset_ptr = &offsets[0];
-  glBufferData(GL_ARRAY_BUFFER, offset_sz, offset_ptr, GL_STATIC_DRAW);
-
-  rock_model.instance_mesh();
-
-  // uniform buffer objects
-  u32 ubo_camera_block;
-  glGenBuffers(1, &ubo_camera_block);
-  glBindBuffer(GL_UNIFORM_BUFFER, ubo_camera_block);
-  glBufferData(GL_UNIFORM_BUFFER, 128, NULL, GL_STATIC_DRAW);
-  glBindBuffer(GL_UNIFORM_BUFFER, 0);
-
 	// objects
 	Vec3 model_translations[] = {
 		Vec3{  0.5, 0.0,  0.0}, // 0: origin square
@@ -755,20 +397,9 @@ int main(int argc, char* argv[])
 	
 	Mat4 proj = perspective4m((r32)To_Radian(90.0), (r32)width / (r32)height, 0.1f, 1000.0f);
 
-  u32 block_binding = 0;
-  u32 matrices_ind;
-  matrices_ind = glGetUniformBlockIndex(shader_program, "Matrices");
-  glUniformBlockBinding(shader_program, matrices_ind, block_binding);
-  matrices_ind = glGetUniformBlockIndex(inst_shader_program, "Matrices");
-  glUniformBlockBinding(inst_shader_program, matrices_ind, block_binding);
-  // or glBindBufferBase();
-  glBindBufferRange(GL_UNIFORM_BUFFER, block_binding, ubo_camera_block, 0, 128); 
-
-  Mat4 col_major_proj = to_col_major4m(proj);
-  glBindBuffer(GL_UNIFORM_BUFFER, ubo_camera_block);
-  glBufferSubData(GL_UNIFORM_BUFFER, 64, 64, col_major_proj.buffer);
-  glBindBuffer(GL_UNIFORM_BUFFER, 0);
-	
+  s32 proj_loc;
+  glUniformMatrix4fv(tex_quad_shader.proj_loc, 1, GL_TRUE, proj.buffer);
+
 	glEnable(GL_DEPTH_TEST);
   glEnable(GL_CULL_FACE);
   glCullFace(GL_BACK);
@@ -892,40 +523,39 @@ int main(int argc, char* argv[])
     view = camera_create4m(camera_pos, add3v(camera_pos, camera_look), preset_up_dir);
         
 		// object shader program stuff
-    Mat4 col_major_view = to_col_major4m(view);
-    glBindBuffer(GL_UNIFORM_BUFFER, ubo_camera_block);
-    glBufferSubData(GL_UNIFORM_BUFFER, 0, 64, col_major_view.buffer);
-    glBindBuffer(GL_UNIFORM_BUFFER, 0);
-    
 		time_prev = time_curr;
+    glUniformMatrix4fv(tex_quad_shader.view_loc, 1, GL_TRUE, view.buffer);
 		
 		// OUTPUT
 		glClearColor(1.0f, 0.6f, .6f, 1.0f);
 		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
-		{
-      glUseProgram(shader_program);
-			Vec3 translation_iter = model_translations[0];
-			Mat4 model = init_value4m(1.0);
-      Mat4 model_scale = scaling_matrix4m(5.0f, 5.0f, 5.0f);
-			model = multiply4m(model_scale, model);
-			Mat4 model_translation = translation_matrix4m(translation_iter.x, translation_iter.y, translation_iter.z);
-			model = multiply4m(model_translation, model);
-      u32 model_loc = glGetUniformLocation(shader_program, "Model");
-			glUniformMatrix4fv(model_loc, 1, GL_TRUE, model.buffer);
-      planet_model.draw(shader_program);
-		}
-		{
-      rock_model.draw_instanced(inst_shader_program, instance_count);
-		}
+    {
+      glUseProgram(tex_quad_shader.id);
+      Vec3 pos = model_translations[0];
+      Mat4 translation = translation_matrix4m(pos.x, pos.y, pos.z);
+      glUniformMatrix4fv(tex_quad_shader.model_loc, 1, GL_TRUE, translation.buffer);
+      gl_draw_tex_quad(tex_quad_shader.id, tex_quad1);
+    }
+
+    {
+      glUseProgram(tex_quad_shader.id);
+      Vec3 pos = model_translations[1];
+      Mat4 translation = translation_matrix4m(pos.x, pos.y, pos.z);
+      glUniformMatrix4fv(tex_quad_shader.model_loc, 1, GL_TRUE, translation.buffer);
+      gl_draw_tex_quad(tex_quad_shader.id, tex_quad2);
+    }
 
 		SDL_GL_SwapWindow(window);
 	}
 	
 	// opengl free calls
-	//glDeleteVertexArrays(1, &vao);
-	//glDeleteBuffers(1, &vbo);
-	glDeleteProgram(shader_program);
+  // it is up to the renderer to free everything here
+  // of course I have not bothered to set that up so it does not matter
+	glDeleteVertexArrays(1, &tex_quad1.vao);
+	glDeleteVertexArrays(1, &tex_quad2.vao);
+	glDeleteBuffers(1, &tex_quad1.vao);
+	glDeleteBuffers(1, &tex_quad2.vao);
 	
 	// sdl free calls
 	SDL_GL_DeleteContext(context);