diff options
Diffstat (limited to 'vendor/gioui.org/f32/affine.go')
-rw-r--r-- | vendor/gioui.org/f32/affine.go | 79 |
1 files changed, 34 insertions, 45 deletions
diff --git a/vendor/gioui.org/f32/affine.go b/vendor/gioui.org/f32/affine.go index 44e914b..667f7e9 100644 --- a/vendor/gioui.org/f32/affine.go +++ b/vendor/gioui.org/f32/affine.go @@ -3,6 +3,7 @@ package f32 import ( + "fmt" "math" ) @@ -11,7 +12,7 @@ import ( type Affine2D struct { // in order to make the zero value of Affine2D represent the identity // transform we store it with the identity matrix subtracted, that is - // if the actual transformaiton matrix is: + // if the actual transformation matrix is: // [sx, hx, ox] // [hy, sy, oy] // [ 0, 0, 1] @@ -24,9 +25,9 @@ type Affine2D struct { // in row major order. The rows are: [sx, hx, ox], [hy, sy, oy], [0, 0, 1]. func NewAffine2D(sx, hx, ox, hy, sy, oy float32) Affine2D { return Affine2D{ - a: sx, b: hx, c: ox, - d: hy, e: sy, f: oy, - }.encode() + a: sx - 1, b: hx, c: ox, + d: hy, e: sy - 1, f: oy, + } } // Offset the transformation. @@ -69,14 +70,13 @@ func (a Affine2D) Shear(origin Point, radiansX, radiansY float32) Affine2D { // Mul returns A*B. func (A Affine2D) Mul(B Affine2D) (r Affine2D) { - A, B = A.decode(), B.decode() - r.a = A.a*B.a + A.b*B.d - r.b = A.a*B.b + A.b*B.e - r.c = A.a*B.c + A.b*B.f + A.c - r.d = A.d*B.a + A.e*B.d - r.e = A.d*B.b + A.e*B.e - r.f = A.d*B.c + A.e*B.f + A.f - return r.encode() + r.a = (A.a+1)*(B.a+1) + A.b*B.d - 1 + r.b = (A.a+1)*B.b + A.b*(B.e+1) + r.c = (A.a+1)*B.c + A.b*B.f + A.c + r.d = A.d*(B.a+1) + (A.e+1)*B.d + r.e = A.d*B.b + (A.e+1)*(B.e+1) - 1 + r.f = A.d*B.c + (A.e+1)*B.f + A.f + return r } // Invert the transformation. Note that if the matrix is close to singular @@ -85,70 +85,59 @@ func (a Affine2D) Invert() Affine2D { if a.a == 0 && a.b == 0 && a.d == 0 && a.e == 0 { return Affine2D{a: 0, b: 0, c: -a.c, d: 0, e: 0, f: -a.f} } - a = a.decode() + a.a += 1 + a.e += 1 det := a.a*a.e - a.b*a.d a.a, a.e = a.e/det, a.a/det a.b, a.d = -a.b/det, -a.d/det temp := a.c a.c = -a.a*a.c - a.b*a.f a.f = -a.d*temp - a.e*a.f - return a.encode() + a.a -= 1 + a.e -= 1 + return a } // Transform p by returning a*p. func (a Affine2D) Transform(p Point) Point { - a = a.decode() return Point{ - X: p.X*a.a + p.Y*a.b + a.c, - Y: p.X*a.d + p.Y*a.e + a.f, + X: p.X*(a.a+1) + p.Y*a.b + a.c, + Y: p.X*a.d + p.Y*(a.e+1) + a.f, } } // Elems returns the matrix elements of the transform in row-major order. The // rows are: [sx, hx, ox], [hy, sy, oy], [0, 0, 1]. func (a Affine2D) Elems() (sx, hx, ox, hy, sy, oy float32) { - a = a.decode() - return a.a, a.b, a.c, a.d, a.e, a.f -} - -func (a Affine2D) encode() Affine2D { - // since we store with identity matrix subtracted - a.a -= 1 - a.e -= 1 - return a -} - -func (a Affine2D) decode() Affine2D { - // since we store with identity matrix subtracted - a.a += 1 - a.e += 1 - return a + return a.a + 1, a.b, a.c, a.d, a.e + 1, a.f } func (a Affine2D) scale(factor Point) Affine2D { - a = a.decode() return Affine2D{ - a.a * factor.X, a.b * factor.X, a.c * factor.X, - a.d * factor.Y, a.e * factor.Y, a.f * factor.Y, - }.encode() + (a.a+1)*factor.X - 1, a.b * factor.X, a.c * factor.X, + a.d * factor.Y, (a.e+1)*factor.Y - 1, a.f * factor.Y, + } } func (a Affine2D) rotate(radians float32) Affine2D { sin, cos := math.Sincos(float64(radians)) s, c := float32(sin), float32(cos) - a = a.decode() return Affine2D{ - a.a*c - a.d*s, a.b*c - a.e*s, a.c*c - a.f*s, - a.a*s + a.d*c, a.b*s + a.e*c, a.c*s + a.f*c, - }.encode() + (a.a+1)*c - a.d*s - 1, a.b*c - (a.e+1)*s, a.c*c - a.f*s, + (a.a+1)*s + a.d*c, a.b*s + (a.e+1)*c - 1, a.c*s + a.f*c, + } } func (a Affine2D) shear(radiansX, radiansY float32) Affine2D { tx := float32(math.Tan(float64(radiansX))) ty := float32(math.Tan(float64(radiansY))) - a = a.decode() return Affine2D{ - a.a + a.d*tx, a.b + a.e*tx, a.c + a.f*tx, - a.a*ty + a.d, a.b*ty + a.e, a.f*ty + a.f, - }.encode() + (a.a + 1) + a.d*tx - 1, a.b + (a.e+1)*tx, a.c + a.f*tx, + (a.a+1)*ty + a.d, a.b*ty + (a.e + 1) - 1, a.f*ty + a.f, + } +} + +func (a Affine2D) String() string { + sx, hx, ox, hy, sy, oy := a.Elems() + return fmt.Sprintf("[[%f %f %f] [%f %f %f]]", sx, hx, ox, hy, sy, oy) } |