mirror of
				https://github.com/godotengine/godot.git
				synced 2025-10-30 21:21:10 +00:00 
			
		
		
		
	
		
			
				
	
	
		
			149 lines
		
	
	
	
		
			6.5 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			149 lines
		
	
	
	
		
			6.5 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| // Copyright 2009-2021 Intel Corporation
 | |
| // SPDX-License-Identifier: Apache-2.0
 | |
| 
 | |
| #pragma once
 | |
| 
 | |
| #include "vec2.h"
 | |
| 
 | |
| namespace embree
 | |
| {
 | |
|   ////////////////////////////////////////////////////////////////////////////////
 | |
|   /// 2D Linear Transform (2x2 Matrix)
 | |
|   ////////////////////////////////////////////////////////////////////////////////
 | |
| 
 | |
|   template<typename T> struct LinearSpace2
 | |
|   {
 | |
|     typedef T Vector;
 | |
|     typedef typename T::Scalar Scalar;
 | |
| 
 | |
|     /*! default matrix constructor */
 | |
|     __forceinline LinearSpace2           ( ) {}
 | |
| 
 | |
|     __forceinline LinearSpace2           ( const LinearSpace2& other ) { vx = other.vx; vy = other.vy; }
 | |
|     __forceinline LinearSpace2& operator=( const LinearSpace2& other ) { vx = other.vx; vy = other.vy; return *this; }
 | |
| 
 | |
|     template<typename L1> __forceinline LinearSpace2( const LinearSpace2<L1>& s ) : vx(s.vx), vy(s.vy) {}
 | |
| 
 | |
|     /*! matrix construction from column vectors */
 | |
|     __forceinline LinearSpace2(const Vector& vx, const Vector& vy)
 | |
|       : vx(vx), vy(vy) {}
 | |
| 
 | |
|     /*! matrix construction from row mayor data */
 | |
|     __forceinline LinearSpace2(const Scalar& m00, const Scalar& m01, 
 | |
|                                const Scalar& m10, const Scalar& m11)
 | |
|       : vx(m00,m10), vy(m01,m11) {}
 | |
| 
 | |
|     /*! compute the determinant of the matrix */
 | |
|     __forceinline const Scalar det() const { return vx.x*vy.y - vx.y*vy.x; }
 | |
| 
 | |
|     /*! compute adjoint matrix */
 | |
|     __forceinline const LinearSpace2 adjoint() const { return LinearSpace2(vy.y,-vy.x,-vx.y,vx.x); }
 | |
| 
 | |
|     /*! compute inverse matrix */
 | |
|     __forceinline const LinearSpace2 inverse() const { return adjoint()/det(); }
 | |
| 
 | |
|     /*! compute transposed matrix */
 | |
|     __forceinline const LinearSpace2 transposed() const { return LinearSpace2(vx.x,vx.y,vy.x,vy.y); }
 | |
| 
 | |
|     /*! returns first row of matrix */
 | |
|     __forceinline Vector row0() const { return Vector(vx.x,vy.x); }
 | |
| 
 | |
|     /*! returns second row of matrix */
 | |
|     __forceinline Vector row1() const { return Vector(vx.y,vy.y); }
 | |
| 
 | |
|     ////////////////////////////////////////////////////////////////////////////////
 | |
|     /// Constants
 | |
|     ////////////////////////////////////////////////////////////////////////////////
 | |
| 
 | |
|     __forceinline LinearSpace2( ZeroTy ) : vx(zero), vy(zero) {}
 | |
|     __forceinline LinearSpace2( OneTy ) : vx(one, zero), vy(zero, one) {}
 | |
| 
 | |
|     /*! return matrix for scaling */
 | |
|     static __forceinline LinearSpace2 scale(const Vector& s) {
 | |
|       return LinearSpace2(s.x,   0,
 | |
|                           0  , s.y);
 | |
|     }
 | |
| 
 | |
|     /*! return matrix for rotation */
 | |
|     static __forceinline LinearSpace2 rotate(const Scalar& r) {
 | |
|       Scalar s = sin(r), c = cos(r);
 | |
|       return LinearSpace2(c, -s,
 | |
|                           s,  c);
 | |
|     }
 | |
| 
 | |
|     /*! return closest orthogonal matrix (i.e. a general rotation including reflection) */
 | |
|     LinearSpace2 orthogonal() const 
 | |
|     {
 | |
|       LinearSpace2 m = *this;
 | |
| 
 | |
|       // mirrored?
 | |
|       Scalar mirror(one);
 | |
|       if (m.det() < Scalar(zero)) {
 | |
|         m.vx = -m.vx;
 | |
|         mirror = -mirror;
 | |
|       }
 | |
| 
 | |
|       // rotation
 | |
|       for (int i = 0; i < 99; i++) {
 | |
|         const LinearSpace2 m_next = 0.5 * (m + m.transposed().inverse());
 | |
|         const LinearSpace2 d = m_next - m;
 | |
|         m = m_next;
 | |
|         // norm^2 of difference small enough?
 | |
|         if (max(dot(d.vx, d.vx), dot(d.vy, d.vy)) < 1e-8)
 | |
|           break;
 | |
|       }
 | |
| 
 | |
|       // rotation * mirror_x
 | |
|       return LinearSpace2(mirror*m.vx, m.vy);
 | |
|     }
 | |
| 
 | |
|   public:
 | |
| 
 | |
|     /*! the column vectors of the matrix */
 | |
|     Vector vx,vy;
 | |
|   };
 | |
| 
 | |
|   ////////////////////////////////////////////////////////////////////////////////
 | |
|   // Unary Operators
 | |
|   ////////////////////////////////////////////////////////////////////////////////
 | |
| 
 | |
|   template<typename T> __forceinline LinearSpace2<T> operator -( const LinearSpace2<T>& a ) { return LinearSpace2<T>(-a.vx,-a.vy); }
 | |
|   template<typename T> __forceinline LinearSpace2<T> operator +( const LinearSpace2<T>& a ) { return LinearSpace2<T>(+a.vx,+a.vy); }
 | |
|   template<typename T> __forceinline LinearSpace2<T> rcp       ( const LinearSpace2<T>& a ) { return a.inverse(); }
 | |
| 
 | |
|   ////////////////////////////////////////////////////////////////////////////////
 | |
|   // Binary Operators
 | |
|   ////////////////////////////////////////////////////////////////////////////////
 | |
| 
 | |
|   template<typename T> __forceinline LinearSpace2<T> operator +( const LinearSpace2<T>& a, const LinearSpace2<T>& b ) { return LinearSpace2<T>(a.vx+b.vx,a.vy+b.vy); }
 | |
|   template<typename T> __forceinline LinearSpace2<T> operator -( const LinearSpace2<T>& a, const LinearSpace2<T>& b ) { return LinearSpace2<T>(a.vx-b.vx,a.vy-b.vy); }
 | |
| 
 | |
|   template<typename T> __forceinline LinearSpace2<T> operator*(const typename T::Scalar & a, const LinearSpace2<T>& b) { return LinearSpace2<T>(a*b.vx, a*b.vy); }
 | |
|   template<typename T> __forceinline T               operator*(const LinearSpace2<T>& a, const T              & b) { return b.x*a.vx + b.y*a.vy; }
 | |
|   template<typename T> __forceinline LinearSpace2<T> operator*(const LinearSpace2<T>& a, const LinearSpace2<T>& b) { return LinearSpace2<T>(a*b.vx, a*b.vy); }
 | |
| 
 | |
|   template<typename T> __forceinline LinearSpace2<T> operator/(const LinearSpace2<T>& a, const typename T::Scalar & b) { return LinearSpace2<T>(a.vx/b, a.vy/b); }
 | |
|   template<typename T> __forceinline LinearSpace2<T> operator/(const LinearSpace2<T>& a, const LinearSpace2<T>& b) { return a * rcp(b); }
 | |
| 
 | |
|   template<typename T> __forceinline LinearSpace2<T>& operator *=( LinearSpace2<T>& a, const LinearSpace2<T>& b ) { return a = a * b; }
 | |
|   template<typename T> __forceinline LinearSpace2<T>& operator /=( LinearSpace2<T>& a, const LinearSpace2<T>& b ) { return a = a / b; }
 | |
| 
 | |
|   ////////////////////////////////////////////////////////////////////////////////
 | |
|   /// Comparison Operators
 | |
|   ////////////////////////////////////////////////////////////////////////////////
 | |
| 
 | |
|   template<typename T> __forceinline bool operator ==( const LinearSpace2<T>& a, const LinearSpace2<T>& b ) { return a.vx == b.vx && a.vy == b.vy; }
 | |
|   template<typename T> __forceinline bool operator !=( const LinearSpace2<T>& a, const LinearSpace2<T>& b ) { return a.vx != b.vx || a.vy != b.vy; }
 | |
| 
 | |
|   ////////////////////////////////////////////////////////////////////////////////
 | |
|   /// Output Operators
 | |
|   ////////////////////////////////////////////////////////////////////////////////
 | |
| 
 | |
|   template<typename T> static embree_ostream operator<<(embree_ostream cout, const LinearSpace2<T>& m) {
 | |
|     return cout << "{ vx = " << m.vx << ", vy = " << m.vy << "}";
 | |
|   }
 | |
| 
 | |
|   /*! Shortcuts for common linear spaces. */
 | |
|   typedef LinearSpace2<Vec2f> LinearSpace2f;
 | |
|   typedef LinearSpace2<Vec2fa> LinearSpace2fa;
 | |
| }
 | 
