Merge remote-tracking branch 'origin/cel-67-load-animation-data-from-gltf' into ral

6 files changed, 324 insertions, 114 deletions

diff --git a/src/renderer/backends/backend_opengl.c b/src/renderer/backends/backend_opengl.c
index ffeb051..7467416 100644
--- a/src/renderer/backends/backend_opengl.c
+++ b/src/renderer/backends/backend_opengl.c
@@ -1,4 +1,5 @@
 #include <stdlib.h>
+#include "camera.h"
 #define CEL_PLATFORM_LINUX
 
 #include "defines.h"
@@ -42,6 +43,9 @@ bool gfx_backend_init(renderer *ren) {
 
   return true;
 }
+
+void gfx_backend_draw_frame(renderer *ren, camera *cam, mat4 model, texture *tex) {}
+
 void gfx_backend_shutdown(renderer *ren) {}
 
 void uniform_vec3f(u32 program_id, const char *uniform_name, vec3 *value) {
diff --git a/src/renderer/backends/backend_vulkan.c b/src/renderer/backends/backend_vulkan.c
index 4a4b09e..4d3a14e 100644
--- a/src/renderer/backends/backend_vulkan.c
+++ b/src/renderer/backends/backend_vulkan.c
@@ -145,6 +145,22 @@ typedef struct global_object_uniform {
   f32 padding[32];
 } global_object_uniform;
 
+typedef struct object_uniform {
+  vec4 diffuse_colour;
+  vec4 v_reserved0;
+  vec4 v_reserved1;
+  vec4 v_reserved2;
+} object_uniform;
+
+#define MAX_OBJECT_COUNT 1024
+#define VULKAN_OBJECT_SHADER_DESCRIPTOR_COUNT 1
+
+typedef struct geometry_render_data {
+  u32 id;
+  mat4 model;
+  texture* textures[16];
+} geometry_render_data;
+
 typedef struct vulkan_buffer {
   u64 total_size;
   VkBuffer handle;
@@ -171,6 +187,8 @@ typedef struct vulkan_shader {
 
   // Data that's global for all objects drawn
   global_object_uniform global_ubo;
+  object_uniform object_ubo;
+  vulkan_texture_data* texture_data;
 } vulkan_shader;
 
 typedef struct vulkan_context {
@@ -324,7 +342,7 @@ bool vulkan_graphics_pipeline_create(vulkan_context* context, vulkan_renderpass*
   // Vertex input
   VkVertexInputBindingDescription binding_desc;
   binding_desc.binding = 0;
-  binding_desc.stride = sizeof(vertex_pos);
+  binding_desc.stride = sizeof(vertex);
   binding_desc.inputRate = VK_VERTEX_INPUT_RATE_VERTEX;
 
   VkPipelineVertexInputStateCreateInfo vertex_input_info = {
@@ -436,6 +454,8 @@ bool vulkan_buffer_create(vulkan_context* context, u64 size, VkBufferUsageFlagBi
     vulkan_buffer_bind(context, out_buffer, 0);
   }
 
+  DEBUG("Created buffer.");
+
   return true;
 }
 
@@ -512,11 +532,21 @@ bool vulkan_object_shader_create(vulkan_context* context, vulkan_shader* out_sha
   global_ubo_layout_binding.pImmutableSamplers = 0;
   global_ubo_layout_binding.stageFlags = VK_SHADER_STAGE_VERTEX_BIT;
 
+  VkDescriptorSetLayoutBinding sampler_layout_binding;
+  sampler_layout_binding.binding = 1;
+  sampler_layout_binding.descriptorCount = 1;
+  sampler_layout_binding.descriptorType = VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER;
+  sampler_layout_binding.pImmutableSamplers = 0;
+  sampler_layout_binding.stageFlags = VK_SHADER_STAGE_FRAGMENT_BIT;
+
   VkDescriptorSetLayoutCreateInfo global_layout_info = {
     VK_STRUCTURE_TYPE_DESCRIPTOR_SET_LAYOUT_CREATE_INFO
   };
-  global_layout_info.bindingCount = 1;
-  global_layout_info.pBindings = &global_ubo_layout_binding;
+
+  VkDescriptorSetLayoutBinding bindings[2] = { global_ubo_layout_binding, sampler_layout_binding };
+
+  global_layout_info.bindingCount = 2;
+  global_layout_info.pBindings = bindings;
 
   VK_CHECK(vkCreateDescriptorSetLayout(context->device.logical_device, &global_layout_info,
                                        context->allocator, &out_shader->descriptor_set_layout));
@@ -525,9 +555,15 @@ bool vulkan_object_shader_create(vulkan_context* context, vulkan_shader* out_sha
   global_pool_size.type = VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER;
   global_pool_size.descriptorCount = 3;
 
+  VkDescriptorPoolSize sampler_pool_size;
+  sampler_pool_size.type = VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER;
+  sampler_pool_size.descriptorCount = 3;
+
+  VkDescriptorPoolSize pool_sizes[2] = { global_pool_size, sampler_pool_size };
+
   VkDescriptorPoolCreateInfo pool_info = { VK_STRUCTURE_TYPE_DESCRIPTOR_POOL_CREATE_INFO };
-  pool_info.poolSizeCount = 1;
-  pool_info.pPoolSizes = &global_pool_size;
+  pool_info.poolSizeCount = 2;
+  pool_info.pPoolSizes = pool_sizes;
   pool_info.maxSets = 3;
 
   VK_CHECK(vkCreateDescriptorPool(context->device.logical_device, &pool_info, context->allocator,
@@ -549,12 +585,13 @@ bool vulkan_object_shader_create(vulkan_context* context, vulkan_shader* out_sha
 
   // Attributes
   u32 offset = 0;
-  const i32 attribute_count = 2;
-  VkVertexInputAttributeDescription attribute_descs[2];
+  const i32 attribute_count = 3;
+  VkVertexInputAttributeDescription attribute_descs[3];
   // Position
-  VkFormat formats[2] = { VK_FORMAT_R32G32B32_SFLOAT, VK_FORMAT_R32G32B32_SFLOAT };
+  VkFormat formats[3] = { VK_FORMAT_R32G32B32_SFLOAT, VK_FORMAT_R32G32B32_SFLOAT,
+                          VK_FORMAT_R32G32_SFLOAT };
 
-  u64 sizes[2] = { sizeof(vec3), sizeof(vec3) };
+  u64 sizes[3] = { sizeof(vec3), sizeof(vec3), sizeof(vec2) };
 
   for (u32 i = 0; i < attribute_count; i++) {
     attribute_descs[i].binding = 0;
@@ -629,15 +666,30 @@ void vulkan_object_shader_update_global_state(vulkan_context* context, vulkan_sh
   buffer_info.offset = offset;
   buffer_info.range = range;
 
-  VkWriteDescriptorSet descriptor_write = { VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET };
-  descriptor_write.dstSet = shader->descriptor_sets[image_index];
-  descriptor_write.dstBinding = 0;
-  descriptor_write.dstArrayElement = 0;
-  descriptor_write.descriptorType = VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER;
-  descriptor_write.descriptorCount = 1;
-  descriptor_write.pBufferInfo = &buffer_info;
+  VkDescriptorImageInfo image_info;
+  image_info.imageLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
+  image_info.imageView = shader->texture_data->image.view;
+  image_info.sampler = shader->texture_data->sampler;
+
+  VkWriteDescriptorSet uniform_write = { VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET };
+  uniform_write.dstSet = shader->descriptor_sets[image_index];
+  uniform_write.dstBinding = 0;
+  uniform_write.dstArrayElement = 0;
+  uniform_write.descriptorType = VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER;
+  uniform_write.descriptorCount = 1;
+  uniform_write.pBufferInfo = &buffer_info;
+
+  VkWriteDescriptorSet texture_write = { VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET };
+  texture_write.dstSet = shader->descriptor_sets[image_index];
+  texture_write.dstBinding = 1;
+  texture_write.dstArrayElement = 0;
+  texture_write.descriptorType = VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER;
+  texture_write.descriptorCount = 1;
+  texture_write.pImageInfo = &image_info;
 
-  vkUpdateDescriptorSets(context->device.logical_device, 1, &descriptor_write, 0, 0);
+  VkWriteDescriptorSet writes[2] = { uniform_write, texture_write };
+
+  vkUpdateDescriptorSets(context->device.logical_device, 2, writes, 0, 0);
 
   vkCmdBindDescriptorSets(cmd_buffer, VK_PIPELINE_BIND_POINT_GRAPHICS, shader->pipeline.layout, 0,
                           1, &global_descriptors, 0, 0);
@@ -871,6 +923,10 @@ void vulkan_image_transition_layout(vulkan_context* context, vulkan_command_buff
                                     vulkan_image* image, VkFormat format, VkImageLayout old_layout,
                                     VkImageLayout new_layout) {
   VkImageMemoryBarrier barrier = { VK_STRUCTURE_TYPE_IMAGE_MEMORY_BARRIER };
+void vulkan_image_transition_layout(vulkan_context* context, vulkan_command_buffer* command_buffer,
+                                    vulkan_image* image, VkFormat format, VkImageLayout old_layout,
+                                    VkImageLayout new_layout) {
+  VkImageMemoryBarrier barrier = { VK_STRUCTURE_TYPE_IMAGE_MEMORY_BARRIER };
   barrier.oldLayout = old_layout;
   barrier.newLayout = new_layout;
   barrier.srcQueueFamilyIndex = context->device.graphics_queue_index;
@@ -891,8 +947,10 @@ void vulkan_image_transition_layout(vulkan_context* context, vulkan_command_buff
       new_layout == VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL) {
     barrier.srcAccessMask = 0;
     barrier.dstAccessMask = VK_ACCESS_TRANSFER_WRITE_BIT;
+
     source_stage = VK_PIPELINE_STAGE_TOP_OF_PIPE_BIT;
-    dest_stage = VK_PIPELINE_STAGE_TOP_OF_PIPE_BIT;
+    dest_stage = VK_PIPELINE_STAGE_TRANSFER_BIT;
+
   } else if (old_layout == VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL &&
              new_layout == VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL) {
     barrier.srcAccessMask = VK_ACCESS_TRANSFER_WRITE_BIT;
@@ -912,10 +970,16 @@ void vulkan_image_copy_from_buffer(vulkan_image* image, VkBuffer buffer,
                                    vulkan_command_buffer* command_buffer) {
   VkBufferImageCopy region;
   region.bufferOffset = 0;
+  region.bufferRowLength = 0;
+  region.bufferImageHeight = 0;
   region.imageSubresource.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
   region.imageSubresource.mipLevel = 0;
   region.imageSubresource.baseArrayLayer = 0;
   region.imageSubresource.layerCount = 1;
+  printf("Image details width: %d height %d\n", image->width, image->height);
+  region.imageOffset.x = 0;
+  region.imageOffset.y = 0;
+  region.imageOffset.z = 0;
   region.imageExtent.width = image->width;
   region.imageExtent.height = image->height;
   region.imageExtent.depth = 1;
@@ -938,7 +1002,7 @@ void vulkan_image_create(vulkan_context* context, VkImageType image_type, u32 wi
   image_create_info.extent.width = width;
   image_create_info.extent.height = height;
   image_create_info.extent.depth = 1;
-  image_create_info.mipLevels = 4;
+  image_create_info.mipLevels = 1;
   image_create_info.arrayLayers = 1;
   image_create_info.format = format;
   image_create_info.tiling = tiling;
@@ -947,8 +1011,8 @@ void vulkan_image_create(vulkan_context* context, VkImageType image_type, u32 wi
   image_create_info.samples = VK_SAMPLE_COUNT_1_BIT;
   image_create_info.sharingMode = VK_SHARING_MODE_EXCLUSIVE;
 
-  vkCreateImage(context->device.logical_device, &image_create_info, context->allocator,
-                &out_image->handle);
+  VK_CHECK(vkCreateImage(context->device.logical_device, &image_create_info, context->allocator,
+                         &out_image->handle));
 
   VkMemoryRequirements memory_reqs;
   vkGetImageMemoryRequirements(context->device.logical_device, out_image->handle, &memory_reqs);
@@ -1645,12 +1709,13 @@ bool gfx_backend_init(renderer* ren) {
 
   mesh cube = prim_cube_mesh_create();
 
-  vertex_pos* verts = malloc(sizeof(vertex_pos) * cube.vertices->len);
+  vertex* verts = malloc(sizeof(vertex) * cube.vertices->len);
 
   f32 scale = 3.0;
   for (size_t i = 0; i < cube.vertices->len; i++) {
-    verts[i].pos = vec3_mult(cube.vertices->data[i].position, scale);
+    verts[i].position = vec3_mult(cube.vertices->data[i].position, scale);
     verts[i].normal = cube.vertices->data[i].normal;
+    verts[i].uv = cube.vertices->data[i].uv;
   }
 
   // const f32 s = 1.0;
@@ -1673,14 +1738,16 @@ bool gfx_backend_init(renderer* ren) {
   // u32 indices[6] = { 0, 1, 2, 0, 3, 1 };
 
   upload_data_range(&context, context.device.gfx_command_pool, 0, context.device.graphics_queue,
-                    &context.object_vertex_buffer, 0, sizeof(vertex_pos) * cube.vertices->len,
-                    verts);
+                    &context.object_vertex_buffer, 0, sizeof(vertex) * cube.vertices->len, verts);
   TRACE("Uploaded vertex data");
   upload_data_range(&context, context.device.gfx_command_pool, 0, context.device.graphics_queue,
                     &context.object_index_buffer, 0, sizeof(u32) * cube.indices_len, cube.indices);
   TRACE("Uploaded index data");
   vertex_darray_free(cube.vertices);
   free(cube.indices);
+
+  // upload texture
+
   // --- End test code
 
   INFO("Vulkan renderer initialisation succeeded");
@@ -1746,16 +1813,22 @@ void texture_data_upload(texture* tex) {
   printf("Texture name %s\n", tex->name);
   tex->backend_data = malloc(sizeof(vulkan_texture_data));
   vulkan_texture_data* data = (vulkan_texture_data*)tex->backend_data;
-  VkDeviceSize image_size = tex->width * tex->height * tex->channel_count;
+  printf("Texture (%s) details: \n  width %d\n  height %d\n  channel count %d\n", tex->name,
+         tex->width, tex->height, tex->channel_count);
+  VkDeviceSize image_size = tex->width * tex->height * max(tex->channel_count, 4);
+
+  TRACE("Creating buffer of size %ld", image_size);
 
-  VkFormat image_format = VK_FORMAT_R8G8B8A8_SNORM;
+  VkFormat image_format = VK_FORMAT_R8G8B8A8_SRGB;
 
   VkBufferUsageFlags usage = VK_BUFFER_USAGE_TRANSFER_SRC_BIT;
   VkMemoryPropertyFlags memory_prop_flags =
       VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT;
   vulkan_buffer staging;
   vulkan_buffer_create(&context, image_size, usage, memory_prop_flags, true, &staging);
+  DEBUG("Uploading image data");
   vulkan_buffer_load_data(&context, &staging, 0, image_size, 0, tex->image_data);
+  INFO("Loaded iamge data!");
 
   vulkan_image_create(
       &context, VK_IMAGE_TYPE_2D, tex->width, tex->height, image_format, VK_IMAGE_TILING_OPTIMAL,
@@ -1802,6 +1875,8 @@ void texture_data_upload(texture* tex) {
     ERROR("Error creating texture sampler for image %s", tex->name);
     return;
   }
+
+  tex->image_data = (void*)data;
 }
 
 // TODO: destroy texture
@@ -1844,7 +1919,7 @@ void backend_end_frame(renderer* ren, f32 delta_time) {
       context.queue_complete_semaphores[context.current_frame], context.image_index);
 }
 
-void gfx_backend_draw_frame(renderer* ren, camera* cam, mat4 model) {
+void gfx_backend_draw_frame(renderer* ren, camera* cam, mat4 model, texture* tex) {
   backend_begin_frame(ren, 16.0);
 
   mat4 proj;
@@ -1852,7 +1927,9 @@ void gfx_backend_draw_frame(renderer* ren, camera* cam, mat4 model) {
 
   camera_view_projection(cam, SCR_HEIGHT, SCR_WIDTH, &view, &proj);
 
+  context.object_shader.texture_data = (vulkan_texture_data*)tex->image_data;
   gfx_backend_update_global_state(proj, view, cam->position, vec4(1.0, 1.0, 1.0, 1.0), 0);
+
   vulkan_object_shader_update_object(&context, &context.object_shader, model);
 
   backend_end_frame(ren, 16.0);
diff --git a/src/renderer/render.c b/src/renderer/render.c
index 2b7f95c..b1e2a46 100644
--- a/src/renderer/render.c
+++ b/src/renderer/render.c
@@ -1,4 +1,8 @@
+#include <assert.h>
 #include <stdlib.h>
+#include <string.h>
+#include "animation.h"
+#include "maths_types.h"
 #include "mem.h"
 #include "transform_hierarchy.h"
 #define STB_IMAGE_IMPLEMENTATION
@@ -61,6 +65,9 @@ bool renderer_init(renderer* ren) {
   ren->blinn_phong =
       shader_create_separate("assets/shaders/blinn_phong.vert", "assets/shaders/blinn_phong.frag");
 
+  ren->skinned =
+      shader_create_separate("assets/shaders/skinned.vert", "assets/shaders/blinn_phong.frag");
+
   default_material_init();
 
   return true;
@@ -91,6 +98,22 @@ void default_material_init() {
   texture_data_upload(&DEFAULT_MATERIAL.specular_texture);
 }
 
+void model_destroy(model* model) {
+  TRACE("Freeing all data for model %s", model->name);
+  arena_free_all(&model->animation_data_arena);
+  arena_free_storage(&model->animation_data_arena);
+  mesh_darray_free(model->meshes);
+  material_darray_free(model->materials);
+  if (model->is_uploaded) {
+    // Delete gpu buffer data
+    for (u32 i = 0; i < mesh_darray_len(model->meshes); i++) {
+      // FIXME: dont leak Opengl
+      glDeleteBuffers(1, &model->meshes->data[i].vbo);
+      glDeleteVertexArrays(1, &model->meshes->data[i].vao);
+    }
+  }
+}
+
 typedef struct draw_ctx {
   model_darray* models;
   renderer* ren;
@@ -153,14 +176,8 @@ void draw_mesh(renderer* ren, mesh* mesh, mat4* model_tf, material* mat, mat4* v
   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));
-
+  // upload model, view, and projection matrices
   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);
 
@@ -169,6 +186,89 @@ void draw_mesh(renderer* ren, mesh* mesh, mat4* model_tf, material* mat, mat4* v
   draw_primitives(CEL_PRIMITIVE_TOPOLOGY_TRIANGLE, 0, num_vertices);
 }
 
+void draw_skinned_mesh(renderer* ren, mesh* mesh, transform tf, material* mat, mat4* view,
+                       mat4* proj) {
+  shader lighting_shader = ren->skinned;
+
+  // 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
+
+  // Uniforms
+  uniform_f32(lighting_shader.program_id, "material.shininess", 32.);
+  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);
+  uniform_mat4f(lighting_shader.program_id, "view", view);
+  uniform_mat4f(lighting_shader.program_id, "projection", proj);
+
+  // bone transforms
+  size_t n_bones = mesh->bones->len;
+
+  // for now assume correct ordering
+  mat4* bone_transforms = malloc(n_bones * sizeof(mat4));
+  mat4 parent = mat4_ident();
+  for (int bone_i = 0; bone_i < n_bones; bone_i++) {
+    joint j = mesh->bones->data[bone_i];
+    transform tf = mesh->bones->data[bone_i].transform_components;
+    tf.position.y = -tf.position.y;
+    mat4 local = transform_to_mat(&tf);
+    mat4 inverse = j.inverse_bind_matrix;
+    inverse.data[13] = -inverse.data[13];
+    mat4 intemediate = mat4_mult(local, inverse);
+
+    bone_transforms[bone_i] = intemediate;
+    parent = bone_transforms[bone_i];
+  }
+
+  // premultiply the inverses
+  // for (int bone_i = 0; bone_i < n_bones; bone_i++) {
+  //   joint j = mesh->bones->data[bone_i];
+  //   // bone_transforms[bone_i] = mat4_mult(bone_transforms[bone_i], j.inverse_bind_matrix);
+  //   bone_transforms[bone_i] = mat4_mult(bone_transforms[bone_i], j.inverse_bind_matrix);
+  // }
+
+  glUniformMatrix4fv(glGetUniformLocation(lighting_shader.program_id, "boneMatrices"), n_bones,
+                     GL_FALSE, &bone_transforms->data[0]);
+
+  free(bone_transforms);
+
+  // draw triangles
+  u32 num_vertices = vertex_darray_len(mesh->vertices);
+  draw_primitives(CEL_PRIMITIVE_TOPOLOGY_TRIANGLE, 0, num_vertices);
+}
+
+void draw_skinned_model(renderer* ren, camera* cam, model* model, transform tf, scene* scene) {
+  mat4 view;
+  mat4 proj;
+  camera_view_projection(cam, SCR_HEIGHT, SCR_WIDTH, &view, &proj);
+
+  set_shader(ren->skinned);
+
+  // set camera uniform
+  uniform_vec3f(ren->skinned.program_id, "viewPos", &cam->position);
+  // set light uniforms
+  dir_light_upload_uniforms(ren->skinned, &scene->dir_light);
+  for (int i = 0; i < scene->n_point_lights; i++) {
+    point_light_upload_uniforms(ren->skinned, &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;
+    }
+    // material* mat = &model->materials->data[m->material_index];
+    material* mat = &DEFAULT_MATERIAL;
+    draw_skinned_mesh(ren, m, tf, mat, &view, &proj);
+  }
+}
+
 void model_upload_meshes(renderer* ren, model* model) {
   INFO("Upload mesh vertex data to GPU for model %s", model->name);
 
@@ -184,6 +284,7 @@ void model_upload_meshes(renderer* ren, model* model) {
 
   // upload each mesh to the GPU
   for (int mesh_i = 0; mesh_i < num_meshes; mesh_i++) {
+    mesh mesh = model->meshes->data[mesh_i];
     model->meshes->data[mesh_i].vao = VAOs[mesh_i];
     model->meshes->data[mesh_i].vbo = VBOs[mesh_i];
     // 3. bind buffers
@@ -193,49 +294,53 @@ void model_upload_meshes(renderer* ren, model* model) {
     // 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;
+    size_t static_vertex_size = 2 * sizeof(vec3) + sizeof(vec2);
+    size_t skinned_vertex_size = 2 * sizeof(vec3) + sizeof(vec2) + 4 * sizeof(u32) + sizeof(vec4);
+    size_t vertex_size = mesh.is_skinned ? skinned_vertex_size : static_vertex_size;
+
+    // TRACE("sizeof(vertex) -> %ld, vertex_size -> %ld\n", sizeof(vertex), vertex_size);
+    if (mesh.is_skinned) {
+      assert(vertex_size == (12 + 12 + 8 + 16 + 16));
+    } else {
+      assert(vertex_size == sizeof(vertex));
+      assert(vertex_size == 8 * sizeof(float));
+    }
+
+    size_t buffer_size = vertex_size * num_vertices;
+    u8* bytes = malloc(buffer_size);
+
+    for (int i = 0; i < num_vertices; i++) {
+      u8* p = bytes + vertex_size * i;
+      memcpy(p, &mesh.vertices->data[i], static_vertex_size);
+      if (mesh.is_skinned) {
+        u8* bone_data_offset = p + static_vertex_size;
+        memcpy(bone_data_offset, &mesh.vertex_bone_data->data[i], sizeof(vertex_bone_data));
       }
     }
 
     // 4. upload data
-    glBufferData(GL_ARRAY_BUFFER, sizeof(verts), verts, GL_STATIC_DRAW);
+    glBufferData(GL_ARRAY_BUFFER, buffer_size, bytes, 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);
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, vertex_size, (void*)0);
     glEnableVertexAttribArray(0);
     // normal vector attribute
-    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(3 * sizeof(float)));
+    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, vertex_size, (void*)(3 * sizeof(float)));
     glEnableVertexAttribArray(1);
     // tex coords
-    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(6 * sizeof(float)));
+    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, vertex_size, (void*)(6 * sizeof(float)));
     glEnableVertexAttribArray(2);
+
+    // skinning (optional)
+    if (mesh.is_skinned) {
+      glEnableVertexAttribArray(3);
+      glVertexAttribIPointer(3, 4, GL_INT, vertex_size, (void*)(8 * sizeof(float)));
+
+      glEnableVertexAttribArray(4);
+      glVertexAttribPointer(4, 4, GL_FLOAT, GL_FALSE, vertex_size, (void*)(12 * sizeof(float)));
+    }
   }
 
   INFO("Uploaded %d submeshes with a total of %d vertices\n", num_meshes, total_verts);
@@ -253,7 +358,7 @@ texture texture_data_load(const char* path, bool invert_y) {
   stbi_set_flip_vertically_on_load(invert_y);
 
 #pragma GCC diagnostic ignored "-Wpointer-sign"
-  char* data = stbi_load(path, &width, &height, &num_channels, 0);
+  char* data = stbi_load(path, &width, &height, &num_channels, 0);  // STBI_rgb_alpha);
   if (data) {
     DEBUG("loaded texture: %s", path);
   } else {
diff --git a/src/renderer/render.h b/src/renderer/render.h
index b687ad1..31cf3b0 100644
--- a/src/renderer/render.h
+++ b/src/renderer/render.h
@@ -38,5 +38,9 @@ void draw_mesh(renderer* ren, mesh* mesh, mat4* tf, material* mat, mat4* view, m
 void draw_scene(arena* frame, model_darray* models, renderer* ren, camera* camera,
                 transform_hierarchy* tfh, scene* scene);
 
+void draw_skinned_model(renderer* ren, camera* cam, model* model, transform tf, scene* scene);
+
+void model_destroy(model* model);
+
 // ---
 texture texture_data_load(const char* path, bool invert_y);  // #frontend
diff --git a/src/renderer/render_backend.h b/src/renderer/render_backend.h
index af62f9f..da30bcc 100644
--- a/src/renderer/render_backend.h
+++ b/src/renderer/render_backend.h
@@ -13,7 +13,7 @@
 bool gfx_backend_init(renderer* ren);
 void gfx_backend_shutdown(renderer* ren);
 
-void gfx_backend_draw_frame(renderer* ren, camera* camera, mat4 model);
+void gfx_backend_draw_frame(renderer* ren, camera* camera, mat4 model, texture* tex);
 void gfx_backend_update_global_state(mat4 projection, mat4 view, vec3 view_pos, vec4 ambient_colour,
                                      i32 mode);
 
diff --git a/src/renderer/render_types.h b/src/renderer/render_types.h
index af20999..387ac81 100644
--- a/src/renderer/render_types.h
+++ b/src/renderer/render_types.h
@@ -7,10 +7,11 @@
 //  */
 // #pragma once
 
-// #include "darray.h"
-// #include "maths.h"
-// #include "maths_types.h"
-// #include "str.h"
+#include "animation.h"
+#include "darray.h"
+#include "maths.h"
+#include "maths_types.h"
+#include "str.h"
 
 // struct GLFWwindow;
 
@@ -40,26 +41,27 @@
 //   u64 last_time;
 // } frame_stats;
 
-// typedef struct renderer {
-//   struct GLFWwindow *window; /** Currently all platforms use GLFW*/
-//   void *backend_state;       /** Graphics API-specific state */
-//   renderer_config config;
-//   // shaders
-//   shader blinn_phong;
-// } renderer;
+typedef struct renderer {
+  struct GLFWwindow *window; /** Currently all platforms use GLFW*/
+  void *backend_state;       /** Graphics API-specific state */
+  renderer_config config;
+  // shaders
+  shader blinn_phong;
+  shader skinned;
+} renderer;
 
 // // --- Lighting & Materials
 
-// typedef struct texture {
-//   u32 texture_id;
-//   char name[MAX_TEXTURE_NAME_LEN];
-//   void* image_data;
-//   void* backend_data;
-//   u32 width;
-//   u32 height;
-//   u8 channel_count;
-//   u32 channel_type;
-// } texture;
+typedef struct texture {
+  u32 texture_id;
+  char name[MAX_TEXTURE_NAME_LEN];
+  void *image_data;
+  void *backend_data;
+  u32 width;
+  u32 height;
+  u8 channel_count;
+  u32 channel_type;
+} texture;
 
 // typedef struct blinn_phong_material {
 //   char name[MAX_MATERIAL_NAME_LEN];
@@ -80,10 +82,15 @@
 // extern material DEFAULT_MATERIAL;
 // void default_material_init();
 
-// #ifndef TYPED_MATERIAL_ARRAY
-// KITC_DECL_TYPED_ARRAY(material)  // creates "material_darray"
-// #define TYPED_MATERIAL_ARRAY
-// #endif
+#ifndef TYPED_MATERIAL_ARRAY
+KITC_DECL_TYPED_ARRAY(material)  // creates "material_darray"
+#define TYPED_MATERIAL_ARRAY
+#endif
+
+#ifndef TYPED_ANIMATION_CLIP_ARRAY
+KITC_DECL_TYPED_ARRAY(animation_clip)  // creates "material_darray"
+#define TYPED_ANIMATION_CLIP_ARRAY
+#endif
 
 // // lights
 // typedef struct point_light {
@@ -113,34 +120,47 @@
 //   vec2 uv;
 // } vertex;
 
-// #ifndef TYPED_VERTEX_ARRAY
-// KITC_DECL_TYPED_ARRAY(vertex)  // creates "vertex_darray"
-// #define TYPED_VERTEX_ARRAY
-// #endif
-
-// typedef struct mesh {
-//   vertex_darray *vertices;
-//   u32 vertex_size; /** size in bytes of each vertex including necessary padding */
-//   bool has_indices;
-//   u32 *indices;
-//   u32 indices_len;
-//   size_t material_index;
-//   u32 vbo, vao; /** OpenGL data. TODO: dont leak OpenGL details */
-// } mesh;
+typedef struct vertex_bone_data {
+  vec4u joints; /** @brief 4 indices of joints that influence vectors position */
+  vec4 weights; /** @brief weight (0,1) of each joint */
+} vertex_bone_data;
+
+#include "animation.h"
+#ifndef TYPED_VERTEX_ARRAY
+KITC_DECL_TYPED_ARRAY(vertex)            // creates "vertex_darray"
+KITC_DECL_TYPED_ARRAY(vertex_bone_data)  // creates "skinned_vertex_darray"
+KITC_DECL_TYPED_ARRAY(joint)
+#define TYPED_VERTEX_ARRAY
+#endif
+
+typedef struct mesh {
+  vertex_darray *vertices;
+  vertex_bone_data_darray *vertex_bone_data;  // only used if model needs it
+  joint_darray *bones;
+  bool is_skinned;
+  u32 vertex_size; /** size in bytes of each vertex including necessary padding */
+  bool has_indices;
+  u32 *indices;
+  u32 indices_len;
+  size_t material_index;
+  u32 vbo, vao; /** OpenGL data. TODO: dont leak OpenGL details */
+} mesh;
 
 // #ifndef TYPED_MESH_ARRAY
 // KITC_DECL_TYPED_ARRAY(mesh)  // creates "mesh_darray"
 // #define TYPED_MESH_ARRAY
 // #endif
 
-// typedef struct model {
-//   str8 name;
-//   mesh_darray *meshes;
-//   aabb_3d bbox;
-//   material_darray *materials;
-//   bool is_loaded;
-//   bool is_uploaded;
-// } model;
+typedef struct model {
+  str8 name;
+  mesh_darray *meshes;
+  aabb_3d bbox;
+  material_darray *materials;
+  animation_clip_darray *animations;
+  arena animation_data_arena;
+  bool is_loaded;
+  bool is_uploaded;
+} model;
 
 // #ifndef TYPED_MODEL_ARRAY
 // KITC_DECL_TYPED_ARRAY(model)  // creates "model_darray"