Merge branch 'master' of github.com:omnisci3nce/celeritas-core

1 files changed, 254 insertions, 0 deletions

diff --git a/src/renderer/render.c b/src/renderer/render.c
index 4e9ad89..7884db6 100644
--- a/src/renderer/render.c
+++ b/src/renderer/render.c
@@ -1,16 +1,39 @@
+#define STB_IMAGE_IMPLEMENTATION
+#include <stb_image.h>
+
+#define STB_TRUETYPE_IMPLEMENTATION
+#include <stb_truetype.h>
+
 #include "render.h"
+#include "render_types.h"
 
+#include <glad/glad.h>
 #include <glfw3.h>
 
+#include "defines.h"
 #include "log.h"
+#include "maths.h"
 #include "render_backend.h"
 
+// FIXME: get rid of these and store dynamic screen realestate
+//        in renderer
+#define SCR_WIDTH 1080
+#define SCR_HEIGHT 800
+
+material DEFAULT_MATERIAL = { 0 };
+
 bool renderer_init(renderer* ren) {
   INFO("Renderer init");
 
   // NOTE: all platforms use GLFW at the moment but thats subject to change
   glfwInit();
 
+  DEBUG("init graphics api (OpenGL) backend");
+  glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);
+  glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 1);
+  glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
+  glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
+
   // glfw window creation
   GLFWwindow* window = glfwCreateWindow(ren->config.scr_width, ren->config.scr_height,
                                         ren->config.window_name, NULL, NULL);
@@ -28,6 +51,9 @@ bool renderer_init(renderer* ren) {
     return false;
   }
 
+  ren->blinn_phong =
+      shader_create_separate("assets/shaders/blinn_phong.vert", "assets/shaders/blinn_phong.frag");
+
   return true;
 }
 
@@ -39,4 +65,232 @@ void render_frame_end(renderer* ren) {
   // present frame
   glfwSwapBuffers(ren->window);
   glfwPollEvents();
+}
+
+void default_material_init() {
+  INFO("Load default material")
+  DEFAULT_MATERIAL.ambient_colour = (vec3){ 0.5, 0.5, 0.5 };
+  DEFAULT_MATERIAL.diffuse = (vec3){ 0.8, 0.8, 0.8 };
+  DEFAULT_MATERIAL.specular = (vec3){ 1.0, 1.0, 1.0 };
+  DEFAULT_MATERIAL.diffuse_texture = texture_data_load("assets/textures/white1x1.png", false);
+  DEFAULT_MATERIAL.specular_texture = texture_data_load("assets/textures/black1x1.png", false);
+  DEFAULT_MATERIAL.spec_exponent = 32.0;
+  strcpy(DEFAULT_MATERIAL.name, "Default");
+  texture_data_upload(&DEFAULT_MATERIAL.diffuse_texture);
+  texture_data_upload(&DEFAULT_MATERIAL.specular_texture);
+}
+
+void draw_model(renderer* ren, camera* camera, model* model, transform tf, scene* scene) {
+  // TRACE("Drawing model: %s", model->name);
+  mat4 view;
+  mat4 proj;
+  camera_view_projection(camera, SCR_HEIGHT, SCR_WIDTH, &view, &proj);
+
+  set_shader(ren->blinn_phong);
+
+  // set camera uniform
+  uniform_vec3f(ren->blinn_phong.program_id, "viewPos", &camera->position);
+  // set light uniforms
+  dir_light_upload_uniforms(ren->blinn_phong, &scene->dir_light);
+  for (int i = 0; i < scene->n_point_lights; i++) {
+    point_light_upload_uniforms(ren->blinn_phong, &scene->point_lights[i], '0' + i);
+  }
+
+  for (size_t i = 0; i < mesh_darray_len(model->meshes); i++) {
+    mesh* m = &model->meshes->data[i];
+    if (vertex_darray_len(m->vertices) == 0) {
+      continue;
+    }
+    // TRACE("Drawing mesh %d", i);
+    material* mat = &model->materials->data[m->material_index];
+    draw_mesh(ren, m, tf, mat, &view, &proj);
+  }
+}
+
+void draw_mesh(renderer* ren, mesh* mesh, transform tf, material* mat, mat4* view, mat4* proj) {
+  shader lighting_shader = ren->blinn_phong;
+
+  // bind buffer
+  bind_mesh_vertex_buffer(ren->backend_state, mesh);
+
+  // bind textures
+  bind_texture(lighting_shader, &mat->diffuse_texture, 0);   // bind to slot 0
+  bind_texture(lighting_shader, &mat->specular_texture, 1);  // bind to slot 1
+  uniform_f32(lighting_shader.program_id, "material.shininess", 32.);
+
+  // upload model transform
+  mat4 trans = mat4_translation(tf.position);
+  mat4 rot = mat4_rotation(tf.rotation);
+  mat4 scale = mat4_scale(tf.scale);
+  mat4 model_tf = mat4_mult(trans, mat4_mult(rot, scale));
+
+  uniform_mat4f(lighting_shader.program_id, "model", &model_tf);
+  // upload view & projection matrices
+  uniform_mat4f(lighting_shader.program_id, "view", view);
+  uniform_mat4f(lighting_shader.program_id, "projection", proj);
+
+  // draw triangles
+  u32 num_vertices = vertex_darray_len(mesh->vertices);
+  draw_primitives(CEL_PRIMITIVE_TOPOLOGY_TRIANGLE, 0, num_vertices);
+}
+
+void model_upload_meshes(renderer* ren, model* model) {
+  INFO("Upload mesh vertex data to GPU for model %s", model->name);
+
+  size_t num_meshes = mesh_darray_len(model->meshes);
+  u32 VBOs[num_meshes];
+  u32 VAOs[num_meshes];
+  glGenBuffers(num_meshes, VBOs);
+  glGenVertexArrays(num_meshes, VAOs);
+
+  u64 total_verts = 0;
+
+  TRACE("num meshes %d", num_meshes);
+
+  // upload each mesh to the GPU
+  for (int mesh_i = 0; mesh_i < num_meshes; mesh_i++) {
+    model->meshes->data[mesh_i].vao = VAOs[mesh_i];
+    model->meshes->data[mesh_i].vbo = VBOs[mesh_i];
+    // 3. bind buffers
+    glBindBuffer(GL_ARRAY_BUFFER, VBOs[mesh_i]);
+
+    size_t num_vertices = vertex_darray_len(model->meshes->data[mesh_i].vertices);
+    // TRACE("Uploading vertex array data: %d verts", num_vertices);
+    total_verts += num_vertices;
+
+    // TODO: convert this garbage into a function
+    f32 verts[num_vertices * 8];
+    // for each face
+    for (int i = 0; i < (num_vertices / 3); i++) {
+      // for each vert in face
+      for (int j = 0; j < 3; j++) {
+        size_t stride = (i * 24) + j * 8;
+        // printf("i: %d, stride: %ld, loc %d\n", i, stride, i * 3 + j);
+        vertex vert = model->meshes->data[mesh_i].vertices->data[i];
+        // printf("pos %f %f %f\n", vert.position.x, vert.position.y, vert.position.z);
+        // printf("norm %f %f %f\n", vert.normal.x, vert.normal.y, vert.normal.z);
+        // printf("tex %f %f\n", vert.uv.x, vert.uv.y);
+        verts[stride + 0] =
+            ((vertex*)model->meshes->data[mesh_i].vertices->data)[i * 3 + j].position.x;
+        verts[stride + 1] =
+            ((vertex*)model->meshes->data[mesh_i].vertices->data)[i * 3 + j].position.y;
+        verts[stride + 2] =
+            ((vertex*)model->meshes->data[mesh_i].vertices->data)[i * 3 + j].position.z;
+        verts[stride + 3] =
+            ((vertex*)model->meshes->data[mesh_i].vertices->data)[i * 3 + j].normal.x;
+        verts[stride + 4] =
+            ((vertex*)model->meshes->data[mesh_i].vertices->data)[i * 3 + j].normal.y;
+        verts[stride + 5] =
+            ((vertex*)model->meshes->data[mesh_i].vertices->data)[i * 3 + j].normal.z;
+        verts[stride + 6] = ((vertex*)model->meshes->data[mesh_i].vertices->data)[i * 3 + j].uv.x;
+        verts[stride + 7] = ((vertex*)model->meshes->data[mesh_i].vertices->data)[i * 3 + j].uv.y;
+      }
+    }
+
+    // 4. upload data
+    glBufferData(GL_ARRAY_BUFFER, sizeof(verts), verts, GL_STATIC_DRAW);
+
+    // 5. cont. set mesh vertex layout
+    glBindVertexArray(model->meshes->data[mesh_i].vao);
+    // position attribute
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)0);
+    glEnableVertexAttribArray(0);
+    // normal vector attribute
+    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(3 * sizeof(float)));
+    glEnableVertexAttribArray(1);
+    // tex coords
+    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(6 * sizeof(float)));
+    glEnableVertexAttribArray(2);
+  }
+
+  INFO("Uploaded %d submeshes with a total of %d vertices\n", num_meshes, total_verts);
+
+  // 6. reset buffer
+  glBindBuffer(GL_ARRAY_BUFFER, 0);
+}
+
+texture texture_data_load(const char* path, bool invert_y) {
+  TRACE("Load texture %s", path);
+
+  // load the file data
+  // texture loading
+  int width, height, num_channels;
+  stbi_set_flip_vertically_on_load(invert_y);
+
+#pragma GCC diagnostic ignored "-Wpointer-sign"
+  char* data = stbi_load(path, &width, &height, &num_channels, 0);
+  if (data) {
+    DEBUG("loaded texture: %s", path);
+  } else {
+    WARN("failed to load texture");
+  }
+
+  unsigned int channel_type;
+  if (num_channels == 4) {
+    channel_type = GL_RGBA;
+  } else {
+    channel_type = GL_RGB;
+  }
+
+  return (texture){ .texture_id = 0,
+                    .width = width,
+                    .height = height,
+                    .channel_count = num_channels,
+                    .channel_type = channel_type,
+                    .name = "TODO: Texture names",
+                    .image_data = data };
+}
+
+void texture_data_upload(texture* tex) {
+  printf("Texture name %s\n", tex->name);
+  TRACE("Upload texture data");
+  u32 texture_id;
+  glGenTextures(1, &texture_id);
+  glBindTexture(GL_TEXTURE_2D, texture_id);
+  tex->texture_id = texture_id;
+
+  // set the texture wrapping parameters
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S,
+                  GL_REPEAT);  // set texture wrapping to GL_REPEAT (default wrapping method)
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+  // set texture filtering parameters
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+  glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, tex->width, tex->height, 0, tex->channel_type,
+               GL_UNSIGNED_BYTE, tex->image_data);
+  glGenerateMipmap(GL_TEXTURE_2D);
+  DEBUG("Freeing texture image data after uploading to GPU");
+  // stbi_image_free(tex->image_data);  // data is on gpu now so we dont need it around
+}
+
+void dir_light_upload_uniforms(shader shader, directional_light* light) {
+  uniform_vec3f(shader.program_id, "dirLight.direction", &light->direction);
+  uniform_vec3f(shader.program_id, "dirLight.ambient", &light->ambient);
+  uniform_vec3f(shader.program_id, "dirLight.diffuse", &light->diffuse);
+  uniform_vec3f(shader.program_id, "dirLight.specular", &light->specular);
+}
+
+void point_light_upload_uniforms(shader shader, point_light* light, char index) {
+  char position_str[] = "pointLights[x].position";
+  position_str[12] = (char)index;
+  char ambient_str[] = "pointLights[x].ambient";
+  ambient_str[12] = (char)index;
+  char diffuse_str[] = "pointLights[x].diffuse";
+  diffuse_str[12] = (char)index;
+  char specular_str[] = "pointLights[x].specular";
+  specular_str[12] = (char)index;
+  char constant_str[] = "pointLights[x].constant";
+  constant_str[12] = (char)index;
+  char linear_str[] = "pointLights[x].linear";
+  linear_str[12] = (char)index;
+  char quadratic_str[] = "pointLights[x].quadratic";
+  quadratic_str[12] = (char)index;
+  uniform_vec3f(shader.program_id, position_str, &light->position);
+  uniform_vec3f(shader.program_id, ambient_str, &light->ambient);
+  uniform_vec3f(shader.program_id, diffuse_str, &light->diffuse);
+  uniform_vec3f(shader.program_id, specular_str, &light->specular);
+  uniform_f32(shader.program_id, constant_str, light->constant);
+  uniform_f32(shader.program_id, linear_str, light->linear);
+  uniform_f32(shader.program_id, quadratic_str, light->quadratic);
 }
\ No newline at end of file