4 files changed, 507 insertions, 0 deletions

diff --git a/src/renderer/imm_renderer.c b/src/renderer/imm_renderer.c
new file mode 100644
index 0000000..01cc5bb
--- /dev/null
+++ b/src/renderer/imm_renderer.c
@@ -0,0 +1,192 @@
+#include "imm_renderer_impl.h"
+
+#include <gfx/core.h>
+#include <gfx/llr/llr.h>
+#include <gfx/renderer/imm_renderer.h>
+#include <gfx/util/shader.h>
+
+#include <math/aabb3.h>
+
+#include <assert.h>
+#include <string.h> // memcpy
+
+bool gfx_imm_make(ImmRenderer* renderer, GfxCore* gfxcore, LLR* llr) {
+  assert(renderer);
+  assert(gfxcore);
+  assert(llr);
+
+  const size_t num_triangle_verts = GFX_IMM_MAX_NUM_TRIANGLES * 3;
+
+  renderer->gfxcore = gfxcore;
+  renderer->llr     = llr;
+
+  renderer->triangles = gfx_make_geometry(
+      gfxcore,
+      &(GeometryDesc){.type         = Triangles,
+                      .buffer_usage = BufferDynamic,
+                      .num_verts    = num_triangle_verts,
+                      .positions3d  = (BufferView3d){
+                           .size_bytes = num_triangle_verts * sizeof(vec3)}});
+  if (!renderer->triangles) {
+    goto cleanup;
+  }
+
+  renderer->shader = gfx_make_immediate_mode_shader(gfxcore);
+  if (!renderer->shader) {
+    goto cleanup;
+  }
+
+  gfx_imm_set_colour(renderer, vec4_make(0.0f, 0.0f, 0.0f, 1.0f));
+
+  return true;
+
+cleanup:
+  gfx_imm_destroy(renderer);
+  return false;
+}
+
+void gfx_imm_destroy(ImmRenderer* renderer) {
+  assert(renderer);
+  assert(renderer->gfxcore);
+
+  if (renderer->triangles) {
+    gfx_destroy_geometry(renderer->gfxcore, &renderer->triangles);
+    // TODO: Could also destroy the geometry's buffers here.
+  }
+
+  if (renderer->shader) {
+    gfx_destroy_shader_program(renderer->gfxcore, &renderer->shader);
+  }
+}
+
+void gfx_imm_flush(ImmRenderer* renderer) {
+  assert(renderer);
+
+  if (renderer->num_triangle_verts > 0) {
+    gfx_update_geometry(
+        renderer->triangles,
+        &(GeometryDesc){
+            .num_verts   = renderer->num_triangle_verts,
+            .positions3d = (BufferView3d){
+                                          .data       = renderer->triangle_verts,
+                                          .size_bytes = renderer->num_triangle_verts * sizeof(vec3)}
+    });
+
+    gfx_llr_render_geometry(renderer->llr, renderer->triangles);
+
+    renderer->num_triangle_verts = 0;
+  }
+}
+
+void gfx_imm_start(ImmRenderer* renderer) {
+  assert(renderer);
+
+  // Shader uniforms are applied lazily.
+  // TODO: In the event that gfx_activate_shader_program() activates uniforms
+  //  automatically for convenience, call an overload here that doesn't do so.
+  // gfx_activate_shader_program(renderer->shader);
+  gfx_llr_set_shader(renderer->llr, renderer->shader);
+}
+
+void gfx_imm_end(ImmRenderer* renderer) {
+  assert(renderer);
+
+  gfx_imm_flush(renderer);
+  // gfx_deactivate_shader_program(renderer->shader);
+  gfx_llr_set_shader(renderer->llr, 0);
+}
+
+void gfx_imm_draw_triangles(
+    ImmRenderer* renderer, const vec3 verts[], size_t num_triangles) {
+  assert(renderer);
+  assert(verts);
+  const size_t new_verts = num_triangles * 3;
+  assert(
+      renderer->num_triangle_verts + new_verts <
+      (GFX_IMM_MAX_NUM_TRIANGLES * 3));
+
+  memcpy(
+      renderer->triangle_verts + renderer->num_triangle_verts, verts,
+      new_verts * sizeof(vec3));
+
+  renderer->num_triangle_verts += new_verts;
+}
+
+void gfx_imm_draw_triangle(ImmRenderer* renderer, const vec3 verts[3]) {
+  gfx_imm_draw_triangles(renderer, verts, 1);
+}
+
+void gfx_imm_draw_aabb2(ImmRenderer* renderer, aabb2 box) {
+  assert(renderer);
+
+  // clang-format off
+  const vec3 verts[4] = {
+      vec3_make(box.min.x, box.min.y, 0),    // 3 ---- 2
+      vec3_make(box.max.x, box.min.y, 0),    // |      |
+      vec3_make(box.max.x, box.max.y, 0),    // |      |
+      vec3_make(box.min.x, box.max.y, 0)};   // 0 ---- 1
+  // clang-format on
+
+#define tri(i0, i1, i2) verts[i0], verts[i1], verts[i2]
+  const vec3 tris[6] = {tri(0, 1, 2), tri(0, 2, 3)};
+#undef tri
+
+  gfx_imm_draw_triangles(renderer, tris, 2);
+}
+
+void gfx_imm_draw_aabb3(ImmRenderer* renderer, aabb3 box) {
+  assert(renderer);
+
+  // clang-format off
+  const vec3 vertices[8] = {
+      vec3_make(box.min.x, box.min.y, box.max.z), //     7 ----- 6
+      vec3_make(box.max.x, box.min.y, box.max.z), //    /       /|
+      vec3_make(box.max.x, box.max.y, box.max.z), //   3 ----- 2 |
+      vec3_make(box.min.x, box.max.y, box.max.z), //   |       | |
+      vec3_make(box.min.x, box.min.y, box.min.z), //   | 4 ----- 5
+      vec3_make(box.max.x, box.min.y, box.min.z), //   |/      |/
+      vec3_make(box.max.x, box.max.y, box.min.z), //   0 ----- 1
+      vec3_make(box.min.x, box.max.y, box.min.z)};
+  // clang-format on
+
+  gfx_imm_draw_box3(renderer, vertices);
+}
+
+void gfx_imm_draw_box3(ImmRenderer* renderer, const vec3 vertices[8]) {
+  assert(renderer);
+  assert(vertices);
+
+  //     7 ----- 6
+  //    /       /|
+  //   3 ----- 2 |
+  //   |       | |
+  //   | 4 ----- 5
+  //   |/      |/
+  //   0 ----- 1
+
+#define tri(i0, i1, i2) vertices[i0], vertices[i1], vertices[i2]
+  const vec3 tris[36] = {
+      // Front.
+      tri(0, 1, 2), tri(0, 2, 3),
+      // Right.
+      tri(1, 5, 6), tri(1, 6, 2),
+      // Back.
+      tri(5, 4, 7), tri(5, 7, 6),
+      // Left.
+      tri(4, 0, 03), tri(4, 3, 7),
+      // Top.
+      tri(3, 2, 6), tri(3, 6, 7),
+      // Bottom.
+      tri(0, 4, 5), tri(0, 5, 1)};
+
+  gfx_imm_draw_triangles(renderer, tris, 12);
+}
+
+void gfx_imm_set_colour(ImmRenderer* renderer, vec4 colour) {
+  assert(renderer);
+  assert(renderer->shader);
+
+  gfx_imm_flush(renderer);
+
+  gfx_set_vec4_uniform(renderer->shader, "Colour", colour);
+}
diff --git a/src/renderer/imm_renderer_impl.h b/src/renderer/imm_renderer_impl.h
new file mode 100644
index 0000000..61b49a7
--- /dev/null
+++ b/src/renderer/imm_renderer_impl.h
@@ -0,0 +1,43 @@
+#pragma once
+
+#include <gfx/sizes.h>
+
+#include <math/vec3.h>
+
+#include <stdbool.h>
+#include <stddef.h>
+
+typedef struct Geometry      Geometry;
+typedef struct GfxCore       GfxCore;
+typedef struct IBL           IBL;
+typedef struct LLR           LLR;
+typedef struct Material      Material;
+typedef struct ShaderProgram ShaderProgram;
+typedef struct Texture       Texture;
+
+/// Immediate mode renderer.
+///
+/// Currently, the immediate mode renderer can only draw up to a maximum number
+/// of primitives per frame. It does not adjust this number dynamically. Keeps
+/// things simple while the extra complexity is not needed.
+/// TODO: Flush the buffer when it reaches its maximum size to remove this
+///  constraint.
+typedef struct ImmRenderer {
+  GfxCore* gfxcore;
+  LLR*     llr;
+
+  ShaderProgram* shader; // Immediate-mode shader program for primitives.
+  Geometry*      triangles;
+  size_t         num_triangle_verts; // Number of triangle verts this frame.
+  // TODO: wireframe rendering.
+  struct {
+    bool wireframe : 1;
+  } flags;
+  vec3 triangle_verts[GFX_IMM_MAX_NUM_TRIANGLES * 3];
+} ImmRenderer;
+
+/// Create a new immediate mode renderer.
+bool gfx_imm_make(ImmRenderer*, GfxCore*, LLR*);
+
+/// Destroy the immediate mode renderer.
+void gfx_imm_destroy(ImmRenderer*);
diff --git a/src/renderer/renderer.c b/src/renderer/renderer.c
new file mode 100644
index 0000000..29a1813
--- /dev/null
+++ b/src/renderer/renderer.c
@@ -0,0 +1,247 @@
+#include "renderer_impl.h"
+
+#include "llr/light_impl.h"
+#include "llr/mesh_impl.h"
+#include "scene/animation_impl.h"
+#include "scene/camera_impl.h"
+#include "scene/model_impl.h"
+#include "scene/node_impl.h"
+#include "scene/object_impl.h"
+#include "scene/scene_impl.h"
+#include "scene/scene_memory.h"
+
+#include <gfx/core.h>
+#include <gfx/llr/llr.h>
+#include <gfx/util/shader.h>
+
+#include <math/mat4.h>
+
+#include <assert.h>
+
+bool gfx_renderer_make(Renderer* renderer, LLR* llr, GfxCore* gfxcore) {
+  assert(renderer);
+  assert(llr);
+  assert(gfxcore);
+
+  renderer->gfxcore = gfxcore;
+  renderer->llr     = llr;
+
+  return true;
+}
+
+void gfx_renderer_destroy(Renderer* renderer) {
+  if (!renderer) {
+    return;
+  }
+  assert(renderer->gfxcore);
+  GfxCore* gfxcore = renderer->gfxcore;
+  if (renderer->shaders.debug) {
+    gfx_destroy_shader_program(gfxcore, &renderer->shaders.debug);
+  }
+  if (renderer->shaders.normals) {
+    gfx_destroy_shader_program(gfxcore, &renderer->shaders.normals);
+  }
+  if (renderer->shaders.normal_mapped_normals) {
+    gfx_destroy_shader_program(
+        gfxcore, &renderer->shaders.normal_mapped_normals);
+  }
+  if (renderer->shaders.tangents) {
+    gfx_destroy_shader_program(gfxcore, &renderer->shaders.tangents);
+  }
+}
+
+static ShaderProgram* load_shader(Renderer* renderer, RenderSceneMode mode) {
+  assert(renderer);
+
+#define LOAD_AND_RETURN(pShader, constructor)   \
+  {                                             \
+    if (!pShader) {                             \
+      pShader = constructor(renderer->gfxcore); \
+    }                                           \
+    assert(pShader);                            \
+    return pShader;                             \
+  }
+
+  switch (mode) {
+  case RenderDefault:
+    return 0;
+  case RenderDebug:
+    LOAD_AND_RETURN(renderer->shaders.debug, gfx_make_debug3d_shader);
+  case RenderNormals:
+    LOAD_AND_RETURN(renderer->shaders.normals, gfx_make_view_normals_shader);
+  case RenderNormalMappedNormals:
+    LOAD_AND_RETURN(
+        renderer->shaders.normal_mapped_normals,
+        gfx_make_view_normal_mapped_normals_shader);
+  case RenderTangents:
+    LOAD_AND_RETURN(renderer->shaders.tangents, gfx_make_view_tangents_shader);
+  }
+  assert(false);
+  return 0;
+}
+
+// static void log_matrix(const mat4* m) {
+//   for (int row = 0; row < 4; ++row) {
+//     LOGI("[ %5.2f, %5.2f, %5.2f, %5.2f ]", m->val[0][row], m->val[1][row],
+//          m->val[2][row], m->val[3][row]);
+//   }
+// }
+
+typedef struct RenderState {
+  GfxCore*       gfxcore;
+  LLR*           llr;
+  Renderer*      renderer;
+  ShaderProgram* shader; // Null to use scene shaders.
+  const Scene*   scene;
+  const Anima*   anima;
+} RenderState;
+
+static void draw_children(
+    RenderState* state, const mat4* node_transform, const SceneNode* node);
+
+/// Draw the scene recursively.
+static void draw_recursively(
+    RenderState* state, mat4 parent_transform, const SceneNode* node) {
+  assert(state);
+  const mat4 node_transform = mat4_mul(parent_transform, node->transform);
+
+  // Anima.
+  if (node->type == AnimaNode) {
+    // Save the anima so that we can animate objects.
+    state->anima = gfx_get_node_anima(node);
+
+    draw_children(state, &node_transform, node);
+  }
+  // Activate light.
+  else if (node->type == LightNode) {
+    Light* light = mem_get_light(node->light);
+    assert(light);
+    gfx_llr_push_light(state->llr, light);
+    {
+      draw_children(state, &node_transform, node);
+    }
+    gfx_llr_pop_light(state->llr);
+  }
+  // Model.
+  else if (node->type == ModelNode) {
+    const Model*     model = gfx_get_node_model(node);
+    const SceneNode* root  = mem_get_node(model->root);
+    draw_recursively(state, parent_transform, root);
+    draw_children(state, &node_transform, node);
+  }
+  // Render object.
+  else if (node->type == ObjectNode) {
+    const SceneObject* object = mem_get_object(node->object);
+    assert(object);
+
+    // TODO: Here we would frustum-cull the object.
+
+    // A model/anima can have many skeletons. We need to animate the given
+    // object using its skeleton, not just any skeleton of the anima.
+    if (object->skeleton.val) {
+      const Skeleton* skeleton = mem_get_skeleton(object->skeleton);
+      gfx_llr_set_skeleton(state->llr, state->anima, skeleton);
+    }
+
+    const mat4 model_matrix = node_transform;
+
+    for (mesh_link_idx mesh_link_index = object->mesh_link;
+         mesh_link_index.val;) {
+      const MeshLink* mesh_link = mem_get_mesh_link(mesh_link_index);
+      mesh_link_index           = mesh_link->next;
+
+      const Mesh* mesh = mem_get_mesh(mesh_link->mesh);
+      if (!mesh) {
+        continue;
+      }
+
+      // TODO: Here we would frustum-cull the mesh. The AABB would have to be
+      //  transformed by the model matrix. Rotation would make the AABB
+      //  relatively large, but still, the culling would be conservative.
+
+      ShaderProgram* shader = state->shader ? state->shader : mesh->shader;
+      gfx_llr_set_shader(state->llr, shader);
+      gfx_llr_set_model_matrix(state->llr, &model_matrix);
+      gfx_llr_render_mesh(state->llr, mesh);
+    }
+
+    if (object->skeleton.val) {
+      gfx_llr_clear_skeleton(state->llr);
+    }
+
+    draw_children(state, &node_transform, node);
+  } else {
+    draw_children(state, &node_transform, node);
+  }
+}
+
+/// Draw the node's children.
+static void draw_children(
+    RenderState* state, const mat4* node_transform, const SceneNode* node) {
+  // Render children recursively.
+  for (node_idx child_index = node->child; child_index.val;) {
+    const SceneNode* child = mem_get_node(child_index);
+    draw_recursively(state, *node_transform, child);
+    child_index = child->next;
+  }
+}
+
+void gfx_render_scene(Renderer* renderer, const RenderSceneParams* params) {
+  assert(renderer);
+  assert(params);
+  assert(params->scene);
+
+  ShaderProgram* const shader = load_shader(renderer, params->mode);
+
+  const Scene*       scene   = params->scene;
+  const SceneCamera* camera  = params->camera;
+  GfxCore* const     gfxcore = renderer->gfxcore;
+
+  int x, y, width, height;
+  gfx_get_viewport(gfxcore, &x, &y, &width, &height);
+  const R aspect = (R)width / (R)height;
+
+  RenderState state = {
+      .gfxcore  = gfxcore,
+      .llr      = renderer->llr,
+      .renderer = renderer,
+      .shader   = shader,
+      .scene    = scene};
+
+  gfx_llr_set_camera(renderer->llr, &camera->camera);
+  gfx_llr_set_aspect(renderer->llr, aspect);
+  draw_recursively(&state, mat4_id(), scene->root);
+}
+
+static void update_rec(SceneNode* node, const SceneCamera* camera, R t) {
+  assert(node);
+  assert(camera);
+
+  const NodeType node_type = gfx_get_node_type(node);
+
+  // TODO: Models do not need to be animated if they are not visible to the
+  //  camera.
+  if (node_type == AnimaNode) {
+    Anima* anima = gfx_get_node_anima_mut(node);
+    gfx_update_animation(anima, (R)t);
+  } else if (node_type == ModelNode) {
+    Model*     model = gfx_get_node_model_mut(node);
+    SceneNode* root  = gfx_get_model_root_mut(model);
+    update_rec(root, camera, t);
+  }
+
+  // Children.
+  SceneNode* child = gfx_get_node_child_mut(node);
+  while (child) {
+    update_rec(child, camera, t);
+    child = gfx_get_node_sibling_mut(child);
+  }
+}
+
+void gfx_update(Scene* scene, const SceneCamera* camera, R t) {
+  assert(scene);
+  assert(camera);
+
+  SceneNode* node = gfx_get_scene_root(scene);
+  update_rec(node, camera, t);
+}
diff --git a/src/renderer/renderer_impl.h b/src/renderer/renderer_impl.h
new file mode 100644
index 0000000..7395915
--- /dev/null
+++ b/src/renderer/renderer_impl.h
@@ -0,0 +1,25 @@
+#pragma once
+
+#include <gfx/renderer.h>
+
+#include <stdbool.h>
+
+typedef struct LLR           LLR;
+typedef struct ShaderProgram ShaderProgram;
+
+typedef struct Renderer {
+  GfxCore* gfxcore;
+  LLR*     llr;
+  struct {
+    ShaderProgram* debug;
+    ShaderProgram* normals;
+    ShaderProgram* normal_mapped_normals;
+    ShaderProgram* tangents;
+  } shaders;
+} Renderer;
+
+/// Create a new renderer.
+bool gfx_renderer_make(Renderer*, LLR*, GfxCore*);
+
+/// Destroy the renderer.
+void gfx_renderer_destroy(Renderer*);