From ac238b3bd63e47a334c6859ddb6570b89f7be3dc Mon Sep 17 00:00:00 2001
From: Matthew Olsson <matthewcolsson@gmail.com>
Date: Mon, 12 Apr 2021 11:20:55 -0700
Subject: [PATCH] LibGfx: Add some helper methods to AffineTransform

Also makes some basic getters ALWAYS_INLINE and [[nodiscard]], as well
as fixing as error with the map method.
---
 Userland/Libraries/LibGfx/AffineTransform.cpp | 67 +++++++++++++++++--
 Userland/Libraries/LibGfx/AffineTransform.h   | 35 +++++++---
 2 files changed, 90 insertions(+), 12 deletions(-)

diff --git a/Userland/Libraries/LibGfx/AffineTransform.cpp b/Userland/Libraries/LibGfx/AffineTransform.cpp
index f711df8dff..2b02f1bac5 100644
--- a/Userland/Libraries/LibGfx/AffineTransform.cpp
+++ b/Userland/Libraries/LibGfx/AffineTransform.cpp
@@ -31,6 +31,26 @@ float AffineTransform::y_scale() const
     return hypotenuse(m_values[2], m_values[3]);
 }
 
+FloatPoint AffineTransform::scale() const
+{
+    return { x_scale(), y_scale() };
+}
+
+float AffineTransform::x_translation() const
+{
+    return e();
+}
+
+float AffineTransform::y_translation() const
+{
+    return f();
+}
+
+FloatPoint AffineTransform::translation() const
+{
+    return { x_translation(), y_translation() };
+}
+
 AffineTransform& AffineTransform::scale(float sx, float sy)
 {
     m_values[0] *= sx;
@@ -40,6 +60,25 @@ AffineTransform& AffineTransform::scale(float sx, float sy)
     return *this;
 }
 
+AffineTransform& AffineTransform::scale(const FloatPoint& s)
+{
+    return scale(s.x(), s.y());
+}
+
+AffineTransform& AffineTransform::set_scale(float sx, float sy)
+{
+    m_values[0] = sx;
+    m_values[1] = 0;
+    m_values[2] = 0;
+    m_values[3] = sy;
+    return *this;
+}
+
+AffineTransform& AffineTransform::set_scale(const FloatPoint& s)
+{
+    return set_scale(s.x(), s.y());
+}
+
 AffineTransform& AffineTransform::translate(float tx, float ty)
 {
     m_values[4] += tx * m_values[0] + ty * m_values[2];
@@ -47,6 +86,23 @@ AffineTransform& AffineTransform::translate(float tx, float ty)
     return *this;
 }
 
+AffineTransform& AffineTransform::translate(const FloatPoint& t)
+{
+    return translate(t.x(), t.y());
+}
+
+AffineTransform& AffineTransform::set_translation(float tx, float ty)
+{
+    m_values[4] = tx;
+    m_values[5] = ty;
+    return *this;
+}
+
+AffineTransform& AffineTransform::set_translation(const FloatPoint& t)
+{
+    return set_translation(t.x(), t.y());
+}
+
 AffineTransform& AffineTransform::multiply(const AffineTransform& other)
 {
     AffineTransform result;
@@ -71,8 +127,8 @@ AffineTransform& AffineTransform::rotate_radians(float radians)
 
 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]);
-    mapped_y = (m_values[1] * unmapped_x + m_values[3] * unmapped_y + m_values[5]);
+    mapped_x = a() * unmapped_x + b() * unmapped_y + m_values[4];
+    mapped_y = c() * unmapped_x + d() * unmapped_y + m_values[5];
 }
 
 template<>
@@ -80,7 +136,7 @@ IntPoint AffineTransform::map(const IntPoint& point) const
 {
     float mapped_x;
     float mapped_y;
-    map(point.x(), point.y(), mapped_x, mapped_y);
+    map(static_cast<float>(point.x()), static_cast<float>(point.y()), mapped_x, mapped_y);
     return { roundf(mapped_x), roundf(mapped_y) };
 }
 
@@ -96,7 +152,10 @@ FloatPoint AffineTransform::map(const FloatPoint& point) const
 template<>
 IntSize AffineTransform::map(const IntSize& size) const
 {
-    return { roundf(size.width() * x_scale()), roundf(size.height() * y_scale()) };
+    return {
+        roundf(static_cast<float>(size.width()) * x_scale()),
+        roundf(static_cast<float>(size.height()) * y_scale()),
+    };
 }
 
 template<>
diff --git a/Userland/Libraries/LibGfx/AffineTransform.h b/Userland/Libraries/LibGfx/AffineTransform.h
index 3e2642f40d..63277b1049 100644
--- a/Userland/Libraries/LibGfx/AffineTransform.h
+++ b/Userland/Libraries/LibGfx/AffineTransform.h
@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <AK/Format.h>
 #include <AK/Forward.h>
 #include <LibGfx/Forward.h>
 
@@ -36,18 +37,28 @@ public:
     template<typename T>
     Rect<T> map(const Rect<T>&) const;
 
-    float a() const { return m_values[0]; }
-    float b() const { return m_values[1]; }
-    float c() const { return m_values[2]; }
-    float d() const { return m_values[3]; }
-    float e() const { return m_values[4]; }
-    float f() const { return m_values[5]; }
+    [[nodiscard]] ALWAYS_INLINE float a() const { return m_values[0]; }
+    [[nodiscard]] ALWAYS_INLINE float b() const { return m_values[1]; }
+    [[nodiscard]] ALWAYS_INLINE float c() const { return m_values[2]; }
+    [[nodiscard]] ALWAYS_INLINE float d() const { return m_values[3]; }
+    [[nodiscard]] ALWAYS_INLINE float e() const { return m_values[4]; }
+    [[nodiscard]] ALWAYS_INLINE float f() const { return m_values[5]; }
 
-    float x_scale() const;
-    float y_scale() const;
+    [[nodiscard]] float x_scale() const;
+    [[nodiscard]] float y_scale() const;
+    [[nodiscard]] FloatPoint scale() const;
+    [[nodiscard]] float x_translation() const;
+    [[nodiscard]] float y_translation() const;
+    [[nodiscard]] FloatPoint translation() const;
 
     AffineTransform& scale(float sx, float sy);
+    AffineTransform& scale(const FloatPoint& s);
+    AffineTransform& set_scale(float sx, float sy);
+    AffineTransform& set_scale(const FloatPoint& s);
     AffineTransform& translate(float tx, float ty);
+    AffineTransform& translate(const FloatPoint& t);
+    AffineTransform& set_translation(float tx, float ty);
+    AffineTransform& set_translation(const FloatPoint& t);
     AffineTransform& rotate_radians(float);
     AffineTransform& multiply(const AffineTransform&);
 
@@ -56,3 +67,11 @@ private:
 };
 
 }
+
+template<>
+struct AK::Formatter<Gfx::AffineTransform> : Formatter<FormatString> {
+    void format(FormatBuilder& builder, Gfx::AffineTransform value)
+    {
+        return Formatter<FormatString>::format(builder, "[{} {} {} {} {} {}]", value.a(), value.b(), value.c(), value.d(), value.e(), value.f());
+    }
+};