fixed perspective, added plane

8 files changed, 75 insertions, 73 deletions

diff --git a/src/engine.cpp b/src/engine.cpp
index adfe43a..96dfd7b 100644
--- a/src/engine.cpp
+++ b/src/engine.cpp
@@ -54,22 +54,17 @@ static void usage_error_exit() {
 }
 
 static void scene_main(engine::Renderer& renderer, engine::math::Matrix4 final_transform_mat, std::function<bool()> update_frame) {
-    float dist = 4.f;
+    float dist = 1.5f;
     float rad = 5.f;
     bool cont = true;
     engine::o3d::Scene scene{
         {{0.f, 0.f, rad * dist}, 0.f, 0.f, 0.f}, // camera
         { // objects
             engine::o3d::Object3D{
-                engine::o3d::Mesh::cube(),
+                engine::o3d::Mesh::plane(),
                 -rad * engine::math::Vector3(.5f, .5f, .5f),
                 rad, 0.f, 0.f, 0.f
             },
-            engine::o3d::Object3D{
-                engine::o3d::Mesh::cube(),
-                +rad * engine::math::Vector3(.5f, .5f, .5f),
-                rad, 0.f, 0.f, 0.f
-            },
         }
     };
     auto scale_mat = engine::math::Matrix4::scale(rad);
@@ -84,13 +79,12 @@ static void scene_main(engine::Renderer& renderer, engine::math::Matrix4 final_t
             * engine::math::Matrix4::rot_x(-scene.camera.rot_x)
             * engine::math::Matrix4::rot_y(-scene.camera.rot_y)
             * engine::math::Matrix4::rot_z(-scene.camera.rot_z);
-        std::array<engine::math::Matrix4, 2> mats{{
-            transform_mat * engine::math::Matrix4::translate(engine::math::Vector3{-.5f * rad, -.5f * rad, -.5f * rad}) * scale_mat,
-            transform_mat * engine::math::Matrix4::translate(engine::math::Vector3{+.5f * rad, +.5f * rad, +.5f * rad}) * scale_mat,
+        std::array<engine::math::Matrix4, 1> mats{{
+            transform_mat * scale_mat,
         }};
         auto pre_final_mat = final_transform_mat
             * engine::math::Matrix4::projection(static_cast<float>(renderer.height()) / static_cast<float>(renderer.width()), 2.f, 50.f);
-        for (int i = 0; i < 2; i++) {
+        for (int i = 0; i < 1; i++) {
             auto final_mat = pre_final_mat * mats[i];
             const auto& mesh = scene.objs[i].mesh;
             std::vector<engine::o3d::Vertex4> pts;
diff --git a/src/fb/pixfb.cpp b/src/fb/pixfb.cpp
index 54da87f..10f2d02 100644
--- a/src/fb/pixfb.cpp
+++ b/src/fb/pixfb.cpp
@@ -34,8 +34,10 @@ void PixelFrameBuffer::clear() {
 }
 
 void PixelFrameBuffer::draw_point(int x, int y, engine::math::Vector3 loc, const engine::o3d::VertexData& vd) {
-    (void) vd;
-    pixels_vector[x + y * w] = face_color(0);
+    (void) loc;
+    int ir = ((int) (((float) ((int) (vd.tx * 10.f))) * 25.5f));
+    int ig = ((int) (((float) ((int) (vd.ty * 10.f))) * 25.5f));
+    pixels_vector[x + y * w] = (ir << 24) | (ig << 16) | 0xFFFF;
 }
 
 uint32_t PixelFrameBuffer::face_color(int face_ind) const {
diff --git a/src/o3d/mesh.cpp b/src/o3d/mesh.cpp
index 47a1ea2..bf60cc8 100644
--- a/src/o3d/mesh.cpp
+++ b/src/o3d/mesh.cpp
@@ -6,25 +6,39 @@
 
 using namespace engine::o3d;
 
-Mesh Mesh::cube() {
+// Mesh Mesh::cube() {
+//     return {
+//         {
+//             { engine::math::Vector3(-1.f, -1.f, -1.f), {} },
+//             { engine::math::Vector3(+1.f, -1.f, -1.f), {} },
+//             { engine::math::Vector3(-1.f, +1.f, -1.f), {} },
+//             { engine::math::Vector3(+1.f, +1.f, -1.f), {} },
+//             { engine::math::Vector3(-1.f, -1.f, +1.f), {} },
+//             { engine::math::Vector3(+1.f, -1.f, +1.f), {} },
+//             { engine::math::Vector3(-1.f, +1.f, +1.f), {} },
+//             { engine::math::Vector3(+1.f, +1.f, +1.f), {} },
+//         },
+//         {
+//             { 0, 2, 3 }, { 0, 3, 1 }, // face 1
+//             { 0, 4, 6 }, { 0, 6, 2 }, // face 2
+//             { 0, 1, 5 }, { 0, 5, 4 }, // face 3
+//             { 7, 6, 4 }, { 7, 4, 5 }, // face 4
+//             { 7, 3, 2 }, { 7, 2, 6 }, // face 5
+//             { 7, 5, 1 }, { 7, 1, 3 }, // face 6
+//         }
+//     };
+// }
+
+Mesh Mesh::plane() {
     return {
         {
-            { engine::math::Vector3(-1.f, -1.f, -1.f), {} },
-            { engine::math::Vector3(+1.f, -1.f, -1.f), {} },
-            { engine::math::Vector3(-1.f, +1.f, -1.f), {} },
-            { engine::math::Vector3(+1.f, +1.f, -1.f), {} },
-            { engine::math::Vector3(-1.f, -1.f, +1.f), {} },
-            { engine::math::Vector3(+1.f, -1.f, +1.f), {} },
-            { engine::math::Vector3(-1.f, +1.f, +1.f), {} },
-            { engine::math::Vector3(+1.f, +1.f, +1.f), {} },
+            { engine::math::Vector3(-1.f, 0.f, -1.f), {0.f, 0.f} },
+            { engine::math::Vector3(+1.f, 0.f, -1.f), {1.f, 0.f} },
+            { engine::math::Vector3(+1.f, 0.f, +1.f), {1.f, 1.f} },
+            { engine::math::Vector3(-1.f, 0.f, +1.f), {0.f, 1.f} },
         },
         {
-            { 0, 2, 3 }, { 0, 3, 1 }, // face 1
-            { 0, 4, 6 }, { 0, 6, 2 }, // face 2
-            { 0, 1, 5 }, { 0, 5, 4 }, // face 3
-            { 7, 6, 4 }, { 7, 4, 5 }, // face 4
-            { 7, 3, 2 }, { 7, 2, 6 }, // face 5
-            { 7, 5, 1 }, { 7, 1, 3 }, // face 6
+            { 0, 1, 2 }, { 2, 3, 0 },
         }
     };
 }
diff --git a/src/o3d/mesh.h b/src/o3d/mesh.h
index 579c8b2..34d1e09 100644
--- a/src/o3d/mesh.h
+++ b/src/o3d/mesh.h
@@ -10,7 +10,8 @@ namespace engine::o3d {
 
 class Mesh {
     public:
-        static Mesh cube(); // this function should not be in this file
+//         static Mesh cube(); // this function should not be in this file
+        static Mesh plane(); // this function should not be in this file
 
         std::vector<Vertex3> pts;
         std::vector<std::array<int, 3>> faces;
diff --git a/src/o3d/vertex_data.cpp b/src/o3d/vertex_data.cpp
index ea8c5fd..b05e382 100644
--- a/src/o3d/vertex_data.cpp
+++ b/src/o3d/vertex_data.cpp
@@ -2,21 +2,19 @@
 
 using namespace engine::o3d;
 
-VertexData VertexData::lerp(const VertexData& vd1, const VertexData& vd2, float s) {
-    (void) vd1;
-    (void) vd2;
-    (void) s;
-    return {};
+VertexData VertexData::lerp(const VertexData& vd1, const VertexData& vd2, float b0) {
+    return {
+        b0 * vd1.tx + (1.f - b0) * vd2.tx,
+        b0 * vd1.ty + (1.f - b0) * vd2.ty
+    };
 }
 
-VertexData VertexData::bilerp(const VertexData& vd1, const VertexData& vd2, const VertexData& vd3, float s, float t) {
-    (void) vd1;
-    (void) vd2;
-    (void) vd3;
-    (void) s;
-    (void) t;
-    return {};
+VertexData VertexData::bilerp(const VertexData& vd1, const VertexData& vd2, const VertexData& vd3, float b0, float b1) {
+    return {
+        b0 * vd1.tx + b1 * vd2.tx + (1.f - b0 - b1) * vd3.tx,
+        b0 * vd1.ty + b1 * vd2.ty + (1.f - b0 - b1) * vd3.ty
+    };
 }
 
-VertexData::VertexData() {
+VertexData::VertexData(float tx, float ty) : tx{tx}, ty{ty} {
 }
diff --git a/src/o3d/vertex_data.h b/src/o3d/vertex_data.h
index ec5fa25..b8ed14c 100644
--- a/src/o3d/vertex_data.h
+++ b/src/o3d/vertex_data.h
@@ -5,10 +5,12 @@ namespace engine::o3d {
 
 class VertexData {
     public:
-        static VertexData lerp(const VertexData& vd1, const VertexData& vd2, float s);
-        static VertexData bilerp(const VertexData& vd1, const VertexData& vd2, const VertexData& vd3, float s, float t);
+        static VertexData lerp(const VertexData& vd1, const VertexData& vd2, float b0);
+        static VertexData bilerp(const VertexData& vd1, const VertexData& vd2, const VertexData& vd3, float b0, float b1);
 
-        VertexData();
+        float tx, ty;
+
+        VertexData(float tx, float ty);
 };
 
 }
diff --git a/src/renderer.cpp b/src/renderer.cpp
index 6e170f3..7a32807 100644
--- a/src/renderer.cpp
+++ b/src/renderer.cpp
@@ -31,7 +31,6 @@ unsigned int Renderer::height() const {
 
 void Renderer::clear() {
     std::fill(depth_buf.begin(), depth_buf.end(), 1.f);
-    face_ind = -1;
     fb->clear();
 }
 
@@ -60,8 +59,8 @@ void Renderer::_draw_cropped_triangle(o3d::TriangleVertex4 root, o3d::TriangleDe
             fac_b0 * sorted_vs[0]->point.z + (1.f - fac_b0) * sorted_vs[2]->point.z,
             1.f / (1.f / sorted_vs[0]->point.w + fac * (1.f / sorted_vs[2]->point.w - 1.f / sorted_vs[0]->point.w))
         },
-        sorted_vs[0]->b0 + fac * (sorted_vs[2]->b0 - sorted_vs[0]->b0),
-        sorted_vs[0]->b1 + fac * (sorted_vs[2]->b1 - sorted_vs[0]->b1)
+        fac_b0 * sorted_vs[0]->b0 + (1.f - fac_b0) * sorted_vs[2]->b0,
+        fac_b0 * sorted_vs[0]->b1 + (1.f - fac_b0) * sorted_vs[2]->b1
     };
     if (middle_vr.point.x < middle_vl.point.x) {
         auto temp = middle_vr;
@@ -86,22 +85,19 @@ void Renderer::_draw_cropped_triangle(o3d::TriangleVertex4 root, o3d::TriangleDe
                     float ix = static_cast<float>(x);
                     float t = (ix - xl) / (xr - xl);
                     float sub_bb1 = s * (1.f - t);
-                    float b_fac = 1.f / (
-                        sub_bb0 / sorted_vs[0]->point.w
-                        + sub_bb1 / middle_vl.point.w
-                        + (1.f - sub_bb0 - sub_bb1) / middle_vr.point.w);
+                    float b_fac = 1.f / (sub_bb0 / sorted_vs[0]->point.w + sub_bb1 / middle_vl.point.w + (1.f - sub_bb0 - sub_bb1) / middle_vr.point.w);
                     float sub_b0 = b_fac * sub_bb0 / sorted_vs[0]->point.w;
                     float sub_b1 = b_fac * sub_bb1 / middle_vl.point.w;
+                    float b0 = sub_b0 * sorted_vs[0]->b0 + sub_b1 * middle_vl.b0 + (1.f - sub_b0 - sub_b1) * middle_vr.b0;
+                    float b1 = sub_b0 * sorted_vs[0]->b1 + sub_b1 * middle_vl.b1 + (1.f - sub_b0 - sub_b1) * middle_vr.b1;
                     math::Vector3 loc{
-                        sub_b0 * sorted_vs[0]->point.x + sub_b1 * middle_vl.point.x + (1.f - sub_b0 - sub_b1) * middle_vr.point.x,
-                        sub_b0 * sorted_vs[0]->point.y + sub_b1 * middle_vl.point.y + (1.f - sub_b0 - sub_b1) * middle_vr.point.y,
-                        sub_b0 * sorted_vs[0]->point.z + sub_b1 * middle_vl.point.z + (1.f - sub_b0 - sub_b1) * middle_vr.point.z
+                        b0 * root.vertex1.point.x + b1 * root.vertex2.point.x + (1.f - b0 - b1) * root.vertex3.point.x,
+                        b0 * root.vertex1.point.y + b1 * root.vertex2.point.y + (1.f - b0 - b1) * root.vertex3.point.y,
+                        b0 * root.vertex1.point.z + b1 * root.vertex2.point.z + (1.f - b0 - b1) * root.vertex3.point.z
                     };
                     if (loc.z < depth_buf[x + y * fb->width()]) {
                         depth_buf[x + y * fb->width()] = loc.z;
-                        fb->draw_point(x, y, loc, o3d::VertexData::bilerp(root.vertex1.data, root.vertex2.data, root.vertex3.data,
-                            sub_b0 * sorted_vs[0]->b0 + sub_b1 * middle_vl.b0 + (1.f - sub_b0 - sub_b1) * middle_vr.b0,
-                            sub_b0 * sorted_vs[0]->b1 + sub_b1 * middle_vl.b1 + (1.f - sub_b0 - sub_b1) * middle_vr.b1));
+                        fb->draw_point(x, y, loc, o3d::VertexData::bilerp(root.vertex1.data, root.vertex2.data, root.vertex3.data, b0, b1));
                     }
                 }
             }
@@ -125,22 +121,19 @@ void Renderer::_draw_cropped_triangle(o3d::TriangleVertex4 root, o3d::TriangleDe
                     float ix = static_cast<float>(x);
                     float t = (ix - xl) / (xr - xl);
                     float sub_bb1 = s * (1.f - t);
-                    float b_fac = 1.f / (
-                        sub_bb0 / sorted_vs[2]->point.w
-                        + sub_bb1 / middle_vl.point.w
-                        + (1.f - sub_bb0 - sub_bb1) / middle_vr.point.w);
+                    float b_fac = 1.f / (sub_bb0 / sorted_vs[2]->point.w + sub_bb1 / middle_vl.point.w + (1.f - sub_bb0 - sub_bb1) / middle_vr.point.w);
                     float sub_b0 = b_fac * sub_bb0 / sorted_vs[2]->point.w;
                     float sub_b1 = b_fac * sub_bb1 / middle_vl.point.w;
+                    float b0 = sub_b0 * sorted_vs[2]->b0 + sub_b1 * middle_vl.b0 + (1.f - sub_b0 - sub_b1) * middle_vr.b0;
+                    float b1 = sub_b0 * sorted_vs[2]->b1 + sub_b1 * middle_vl.b1 + (1.f - sub_b0 - sub_b1) * middle_vr.b1;
                     math::Vector3 loc{
-                        sub_b0 * sorted_vs[2]->point.x + sub_b1 * middle_vl.point.x + (1.f - sub_b0 - sub_b1) * middle_vr.point.x,
-                        sub_b0 * sorted_vs[2]->point.y + sub_b1 * middle_vl.point.y + (1.f - sub_b0 - sub_b1) * middle_vr.point.y,
-                        sub_b0 * sorted_vs[2]->point.z + sub_b1 * middle_vl.point.z + (1.f - sub_b0 - sub_b1) * middle_vr.point.z
+                        b0 * root.vertex1.point.x + b1 * root.vertex2.point.x + (1.f - b0 - b1) * root.vertex3.point.x,
+                        b0 * root.vertex1.point.y + b1 * root.vertex2.point.y + (1.f - b0 - b1) * root.vertex3.point.y,
+                        b0 * root.vertex1.point.z + b1 * root.vertex2.point.z + (1.f - b0 - b1) * root.vertex3.point.z
                     };
                     if (loc.z < depth_buf[x + y * fb->width()]) {
                         depth_buf[x + y * fb->width()] = loc.z;
-                        fb->draw_point(x, y, loc, o3d::VertexData::bilerp(root.vertex1.data, root.vertex2.data, root.vertex3.data,
-                            sub_b0 * sorted_vs[2]->b0 + sub_b1 * middle_vl.b0 + (1.f - sub_b0 - sub_b1) * middle_vr.b0,
-                            sub_b0 * sorted_vs[2]->b1 + sub_b1 * middle_vl.b1 + (1.f - sub_b0 - sub_b1) * middle_vr.b1));
+                        fb->draw_point(x, y, loc, o3d::VertexData::bilerp(root.vertex1.data, root.vertex2.data, root.vertex3.data, b0, b1));
                     }
                 }
             }
@@ -149,12 +142,11 @@ void Renderer::_draw_cropped_triangle(o3d::TriangleVertex4 root, o3d::TriangleDe
 }
 
 void Renderer::draw_triangle(o3d::TriangleVertex4 triangle) {
-    face_ind++;
     for (auto t1 : triangle.to_derived().crop_z_out(-1.f, 1.f)) {
         for (auto t2 : t1.div_by_w().perspective_crop_xy_out(-1.f, 1.f, -1.f, 1.f)) {
-            math::Vector2 pp1 = t2.derived_vertex1.point.xy();
-            math::Vector2 pp2 = t2.derived_vertex2.point.xy();
-            math::Vector2 pp3 = t2.derived_vertex3.point.xy();
+            auto pp1 = t2.derived_vertex1.point.xy();
+            auto pp2 = t2.derived_vertex2.point.xy();
+            auto pp3 = t2.derived_vertex3.point.xy();
             if ((pp2 - pp1).det(pp3 - pp1) >= 0.f) continue;
             float fw_over_2 = static_cast<float>(fb->width()) / 2.f, fh_over_2 = static_cast<float>(fb->height()) / 2.f;
             t2.derived_vertex1.point.x = (t2.derived_vertex1.point.x + 1.f) * fw_over_2 - .5f;
diff --git a/src/renderer.h b/src/renderer.h
index a82ad56..046a4ef 100644
--- a/src/renderer.h
+++ b/src/renderer.h
@@ -20,7 +20,6 @@ class Renderer {
 
     private:
         std::vector<float> depth_buf;
-        int face_ind;
 
         void _draw_cropped_triangle(o3d::TriangleVertex4 root, o3d::TriangleDerivedVertex4 triangle);
 };