some code reorganization

[blank.git] / src / world / Block.hpp

diff --git a/src/world/Block.hpp b/src/world/Block.hpp
new file mode 100644 (file)
index 0000000..74af3e4
--- /dev/null
+++ b/src/world/Block.hpp
@@ -0,0 +1,135 @@
+#ifndef BLANK_WORLD_BLOCK_HPP_
+#define BLANK_WORLD_BLOCK_HPP_
+
+#include <glm/glm.hpp>
+
+
+namespace blank {
+
+/// single 1x1x1 cube
+struct Block {
+
+       using Type = unsigned short;
+       using Pos = glm::vec3;
+
+       enum Face {
+               FACE_UP,
+               FACE_DOWN,
+               FACE_RIGHT,
+               FACE_LEFT,
+               FACE_FRONT,
+               FACE_BACK,
+               FACE_COUNT,
+       };
+       enum Turn {
+               TURN_NONE,
+               TURN_LEFT,
+               TURN_AROUND,
+               TURN_RIGHT,
+               TURN_COUNT,
+       };
+
+       static constexpr int ORIENT_COUNT = FACE_COUNT * TURN_COUNT;
+
+       Type type;
+       unsigned char orient;
+
+       constexpr explicit Block(Type type = 0, Face face = FACE_UP, Turn turn = TURN_NONE) noexcept
+       : type(type), orient(face * TURN_COUNT + turn) { }
+
+       const glm::mat4 &Transform() const noexcept { return orient2transform[orient]; }
+
+       Face GetFace() const noexcept { return Face(orient / TURN_COUNT); }
+       void SetFace(Face face) noexcept { orient = face * TURN_COUNT + GetTurn(); }
+       Turn GetTurn() const noexcept { return Turn(orient % TURN_COUNT); }
+       void SetTurn(Turn turn) noexcept { orient = GetFace() * TURN_COUNT + turn; }
+
+       Face OrientedFace(Face f) const noexcept { return orient2face[orient][f]; }
+
+       static Face Opposite(Face f) noexcept {
+               return Face(f ^ 1);
+       }
+
+       static int Axis(Face f) noexcept {
+               switch (f) {
+                       case FACE_UP:
+                       case FACE_DOWN:
+                               return 1;
+                       default:
+                       case FACE_RIGHT:
+                       case FACE_LEFT:
+                               return 0;
+                       case FACE_FRONT:
+                       case FACE_BACK:
+                               return 2;
+               }
+       }
+
+       static glm::tvec3<int> FaceNormal(Face face) noexcept {
+               return face2normal[face];
+       }
+
+       static Face NormalFace(const glm::vec3 &norm) noexcept {
+               const glm::vec3 anorm(abs(norm));
+               if (anorm.x > anorm.y) {
+                       if (anorm.x > anorm.z) {
+                               return norm.x > 0.0f ? FACE_RIGHT : FACE_LEFT;
+                       } else {
+                               return norm.z > 0.0f ? FACE_FRONT : FACE_BACK;
+                       }
+               } else {
+                       if (anorm.y > anorm.z) {
+                               return norm.y > 0.0f ? FACE_UP : FACE_DOWN;
+                       } else {
+                               return norm.z > 0.0f ? FACE_FRONT : FACE_BACK;
+                       }
+               }
+       }
+
+       struct FaceSet {
+
+               explicit FaceSet(unsigned char v = 0)
+               : value(v) { }
+
+               bool IsSet(Face f) const {
+                       return value & Mask(f);
+               }
+               void Set(Face f) {
+                       value |= Mask(f);
+               }
+               void Unset(Face f) {
+                       value |= ~Mask(f);
+               }
+
+               void Clear() {
+                       value = 0;
+               }
+               void Fill() {
+                       value = Mask(FACE_COUNT) - 1;
+               }
+
+               bool Empty() const {
+                       return value == 0;
+               }
+               bool All() const {
+                       return value == Mask(FACE_COUNT) - 1;
+               }
+
+               unsigned char Mask(Face f) const {
+                       return 1 << f;
+               }
+
+               unsigned char value;
+
+       };
+
+private:
+       static const glm::tvec3<int> face2normal[6];
+       static const glm::mat4 orient2transform[ORIENT_COUNT];
+       static const Face orient2face[ORIENT_COUNT][FACE_COUNT];
+
+};
+
+}
+
+#endif