mirrors/ladybird
1
0
Fork 0
mirror of https://github.com/LadybirdBrowser/ladybird.git synced 2025-04-21 20:15:17 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 10

LibGfx: Teach AffineTransform how to rotate and multiply

Browse source
This commit is contained in:
Andreas Kling 2020-06-26 18:23:38 +02:00
parent ba76a72422
commit dc22e59a1a
Notes: sideshowbarker 2024-07-19 05:22:06 +09:00
2 changed files with 29 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

22
Libraries/LibGfx/AffineTransform.cpp
View file

@ -69,6 +69,28 @@ AffineTransform& AffineTransform::translate(float tx, float ty)
return *this;
}
AffineTransform& AffineTransform::multiply(const AffineTransform& other)
{
AffineTransform result;
result.m_values[0] = other.a() * a() + other.b() * c();
result.m_values[1] = other.a() * b() + other.b() * d();
result.m_values[2] = other.c() * a() + other.d() * c();
result.m_values[3] = other.c() * b() + other.d() * d();
result.m_values[4] = other.e() * a() + other.f() * c() + e();
result.m_values[5] = other.e() * b() + other.f() * d() + f();
*this = result;
return *this;
}
AffineTransform& AffineTransform::rotate_radians(float radians)
{
float sin_angle = sinf(radians);
float cos_angle = cosf(radians);
AffineTransform rotation(cos_angle, sin_angle, -sin_angle, cos_angle, 0, 0);
multiply(rotation);
return *this;
}
void AffineTransform::map(float unmapped_x, float unmapped_y, float& mapped_x, float& mapped_y) const
{
mapped_x = (m_values[0] * unmapped_x + m_values[2] * unmapped_y + m_values[4]);

7
Libraries/LibGfx/AffineTransform.h
View file

@ -39,6 +39,11 @@ public:
{
}
AffineTransform(float a, float b, float c, float d, float e, float f)
: m_values { a, b, c, d, e, f }
{
}
bool is_identity() const;
void map(float unmapped_x, float unmapped_y, float& mapped_x, float& mapped_y) const;
@ -64,6 +69,8 @@ public:
AffineTransform& scale(float sx, float sy);
AffineTransform& translate(float tx, float ty);
AffineTransform& rotate_radians(float);
AffineTransform& multiply(const AffineTransform&);
private:
float m_values[6] { 0 };