added textures for the hardware renderer

- removed "using" directive in .hpp
- reverse order of arguments for quaternion rotation, i.e. q.rot(v)
  instead of v.rot(q), where q is a quaterinon and v a vector
- pass the inverse of the view matrix to render_and_present_frame, to
  allow light calculation in shaders (we used to just pass the matrix of
  the quaternion of the transformation, i.e. discard scaling and
  translations)
- added another mesh and texture (viking_room) for testing purposes
- added transparent background option
- added Quaternion::look_towards(), which is the equivalent of
  Matrix4::look_at() but only for rotations
- various improvement to .obj parsing
- load texture coordinates from .obj file
- merged duplicate vertices in Mesh::linearize_indices()

4 files changed, 11 insertions, 15 deletions

diff --git a/src/fb/chfb.cpp b/src/fb/chfb.cpp
index 9f293ed..7341015 100644
--- a/src/fb/chfb.cpp
+++ b/src/fb/chfb.cpp
@@ -8,6 +8,7 @@
 
 using namespace engine::fb;
 using
+    engine::math::Vector2,
     engine::math::Vector3,
     engine::o3d::VertexData,
     engine::o3d::Camera;
@@ -31,10 +32,8 @@ void CharacterFrameBuffer::clear() {
 char brightness_chars[] = " `.-':_,^=;><+!rc*/z?sLTv)J7(|Fi{C}fI31tlu[neoZ5Yxjya]2ESwqkP6h9d4VpOGbUAKXHm8RD#$Bg0MNWQ%&@";
 extern Camera* camera;
 
-void CharacterFrameBuffer::draw_point(int x, int y, const Vector3& loc, const VertexData& vd, const Vector3& normal) {
-    (void) loc;
-    (void) vd;
-    auto v = normal.rot(camera->transform.rot.conjugate());
+void CharacterFrameBuffer::draw_point(int x, int y, const Vector3& /* loc */, const Vector3& normal, const Vector2& /* uv */, const VertexData& /* vd */) {
+    auto v = camera->transform.rot.conjugate().rot(normal).normalize();
     float light = .1f + (v.z < 0.f ? 0.f : v.z) * .9f;
     std::uint32_t c = (int) (light * static_cast<float>(sizeof(brightness_chars) - 1));
     chars_vector[x + y * w] = brightness_chars[c];
diff --git a/src/fb/chfb.hpp b/src/fb/chfb.hpp
index 7f6857b..1748abf 100644
--- a/src/fb/chfb.hpp
+++ b/src/fb/chfb.hpp
@@ -7,14 +7,13 @@
 
 namespace engine::fb {
 
-using engine::math::Vector3, engine::o3d::VertexData;
-
 class CharacterFrameBuffer {
     public:
         CharacterFrameBuffer(unsigned int w, unsigned int h);
         void resize(unsigned int w, unsigned int h);
         void clear();
-        void draw_point(int x, int y, const Vector3& loc, const VertexData& vd, const Vector3& normal);
+        void draw_point(int x, int y, const engine::math::Vector3& loc,
+                const engine::math::Vector3& normal, const engine::math::Vector2& uv, const engine::o3d::VertexData& vd);
 
         constexpr unsigned int width() const & {
             return w;
diff --git a/src/fb/pixfb.cpp b/src/fb/pixfb.cpp
index b38ec30..c629adb 100644
--- a/src/fb/pixfb.cpp
+++ b/src/fb/pixfb.cpp
@@ -8,6 +8,7 @@
 
 using namespace engine::fb;
 using
+    engine::math::Vector2,
     engine::math::Vector3,
     engine::o3d::VertexData,
     engine::o3d::Camera;
@@ -29,17 +30,15 @@ void PixelFrameBuffer::clear() {
 
 extern Camera* camera;
 
-void PixelFrameBuffer::draw_point(int x, int y, const Vector3& loc, const VertexData& vd, const Vector3& normal) {
-    (void) loc;
-    (void) vd;
+void PixelFrameBuffer::draw_point(int x, int y, const Vector3& /* loc */, const Vector3& normal, const Vector2& /* uv */, const VertexData& vd) {
     auto u = vd.world_loc - camera->transform.loc;
     float u_len_sq = u.length_squared();
     u = u.normalize();
-    float attenuation = Vector3(0.f, 0.f, -1.f).rot(camera->transform.rot).dot(u);
+    float attenuation = camera->transform.rot.rot({ 0.f, 0.f, -1.f }).dot(u);
     if (attenuation < .7f) attenuation = 0.f;
     else if (attenuation > .8f) attenuation = 1.f;
     else attenuation = (attenuation - .7f) / .1f;
-    float light = -normal.dot(u) / u_len_sq;
+    float light = -normal.normalize().dot(u) / u_len_sq;
     if (light < 0.f) light = 0.f;
     float final_light = .003f + light * attenuation * .8f * .997f;
     if (final_light > 1.f) final_light = 1.f;
diff --git a/src/fb/pixfb.hpp b/src/fb/pixfb.hpp
index 92fa604..954f6e1 100644
--- a/src/fb/pixfb.hpp
+++ b/src/fb/pixfb.hpp
@@ -8,14 +8,13 @@
 
 namespace engine::fb {
 
-using engine::math::Vector3, engine::o3d::VertexData;
-
 class PixelFrameBuffer {
     public:
         PixelFrameBuffer(unsigned int w, unsigned int h);
         void resize(unsigned int w, unsigned int h);
         void clear();
-        void draw_point(int x, int y, const Vector3& loc, const VertexData& vd, const Vector3& normal);
+        void draw_point(int x, int y, const engine::math::Vector3& loc,
+                const engine::math::Vector3& normal, const engine::math::Vector2& uv, const engine::o3d::VertexData& vd);
 
         constexpr unsigned int width() const & {
             return w;