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	* add back exif-terminator and use only for jpeg,png,webp * fix arguments passed to terminateExif() * pull in latest exif-terminator * fix test * update processed img --------- Co-authored-by: tobi <tobi.smethurst@protonmail.com>
		
			
				
	
	
		
			127 lines
		
	
	
	
		
			4 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			127 lines
		
	
	
	
		
			4 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
| // Copyright 2015 Google Inc. All rights reserved.
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| //
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| // Licensed under the Apache License, Version 2.0 (the "License");
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| // you may not use this file except in compliance with the License.
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| // You may obtain a copy of the License at
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| //
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| //     http://www.apache.org/licenses/LICENSE-2.0
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| //
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| // Unless required by applicable law or agreed to in writing, software
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| // distributed under the License is distributed on an "AS IS" BASIS,
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| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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| // See the License for the specific language governing permissions and
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| // limitations under the License.
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| 
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| package s2
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| 
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| import (
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| 	"fmt"
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| 
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| 	"github.com/golang/geo/r3"
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| )
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| 
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| // matrix3x3 represents a traditional 3x3 matrix of floating point values.
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| // This is not a full fledged matrix. It only contains the pieces needed
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| // to satisfy the computations done within the s2 package.
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| type matrix3x3 [3][3]float64
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| 
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| // col returns the given column as a Point.
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| func (m *matrix3x3) col(col int) Point {
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| 	return Point{r3.Vector{m[0][col], m[1][col], m[2][col]}}
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| }
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| 
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| // row returns the given row as a Point.
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| func (m *matrix3x3) row(row int) Point {
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| 	return Point{r3.Vector{m[row][0], m[row][1], m[row][2]}}
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| }
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| 
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| // setCol sets the specified column to the value in the given Point.
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| func (m *matrix3x3) setCol(col int, p Point) *matrix3x3 {
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| 	m[0][col] = p.X
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| 	m[1][col] = p.Y
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| 	m[2][col] = p.Z
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| 
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| 	return m
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| }
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| 
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| // setRow sets the specified row to the value in the given Point.
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| func (m *matrix3x3) setRow(row int, p Point) *matrix3x3 {
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| 	m[row][0] = p.X
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| 	m[row][1] = p.Y
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| 	m[row][2] = p.Z
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| 
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| 	return m
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| }
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| 
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| // scale multiplies the matrix by the given value.
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| func (m *matrix3x3) scale(f float64) *matrix3x3 {
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| 	return &matrix3x3{
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| 		[3]float64{f * m[0][0], f * m[0][1], f * m[0][2]},
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| 		[3]float64{f * m[1][0], f * m[1][1], f * m[1][2]},
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| 		[3]float64{f * m[2][0], f * m[2][1], f * m[2][2]},
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| 	}
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| }
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| 
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| // mul returns the multiplication of m by the Point p and converts the
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| // resulting 1x3 matrix into a Point.
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| func (m *matrix3x3) mul(p Point) Point {
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| 	return Point{r3.Vector{
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| 		m[0][0]*p.X + m[0][1]*p.Y + m[0][2]*p.Z,
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| 		m[1][0]*p.X + m[1][1]*p.Y + m[1][2]*p.Z,
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| 		m[2][0]*p.X + m[2][1]*p.Y + m[2][2]*p.Z,
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| 	}}
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| }
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| 
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| // det returns the determinant of this matrix.
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| func (m *matrix3x3) det() float64 {
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| 	//      | a  b  c |
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| 	//  det | d  e  f | = aei + bfg + cdh - ceg - bdi - afh
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| 	//      | g  h  i |
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| 	return m[0][0]*m[1][1]*m[2][2] + m[0][1]*m[1][2]*m[2][0] + m[0][2]*m[1][0]*m[2][1] -
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| 		m[0][2]*m[1][1]*m[2][0] - m[0][1]*m[1][0]*m[2][2] - m[0][0]*m[1][2]*m[2][1]
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| }
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| 
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| // transpose reflects the matrix along its diagonal and returns the result.
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| func (m *matrix3x3) transpose() *matrix3x3 {
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| 	m[0][1], m[1][0] = m[1][0], m[0][1]
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| 	m[0][2], m[2][0] = m[2][0], m[0][2]
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| 	m[1][2], m[2][1] = m[2][1], m[1][2]
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| 
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| 	return m
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| }
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| 
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| // String formats the matrix into an easier to read layout.
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| func (m *matrix3x3) String() string {
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| 	return fmt.Sprintf("[ %0.4f %0.4f %0.4f ] [ %0.4f %0.4f %0.4f ] [ %0.4f %0.4f %0.4f ]",
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| 		m[0][0], m[0][1], m[0][2],
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| 		m[1][0], m[1][1], m[1][2],
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| 		m[2][0], m[2][1], m[2][2],
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| 	)
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| }
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| 
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| // getFrame returns the orthonormal frame for the given point on the unit sphere.
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| func getFrame(p Point) matrix3x3 {
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| 	// Given the point p on the unit sphere, extend this into a right-handed
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| 	// coordinate frame of unit-length column vectors m = (x,y,z).  Note that
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| 	// the vectors (x,y) are an orthonormal frame for the tangent space at point p,
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| 	// while p itself is an orthonormal frame for the normal space at p.
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| 	m := matrix3x3{}
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| 	m.setCol(2, p)
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| 	m.setCol(1, Point{p.Ortho()})
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| 	m.setCol(0, Point{m.col(1).Cross(p.Vector)})
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| 	return m
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| }
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| 
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| // toFrame returns the coordinates of the given point with respect to its orthonormal basis m.
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| // The resulting point q satisfies the identity (m * q == p).
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| func toFrame(m matrix3x3, p Point) Point {
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| 	// The inverse of an orthonormal matrix is its transpose.
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| 	return m.transpose().mul(p)
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| }
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| 
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| // fromFrame returns the coordinates of the given point in standard axis-aligned basis
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| // from its orthonormal basis m.
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| // The resulting point p satisfies the identity (p == m * q).
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| func fromFrame(m matrix3x3, q Point) Point {
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| 	return m.mul(q)
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| }
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