Remove optional prepend argument from matrix transformations.

Callers always want one form or the other, so split into separate
methods. This may save some branching.

Remove forms that are not used.
Put more helpful helper function in .cpp file.

Change-Id: I4e025de7f69ce3f323cd290a5dc8202dd4f8ca07
Reviewed-on: https://pdfium-review.googlesource.com/40270
Commit-Queue: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>

5 files changed, 56 insertions, 137 deletions

diff --git a/core/fxcrt/fx_coordinates.cpp b/core/fxcrt/fx_coordinates.cpp
index 13c6f1b6bc..12bf8b6c38 100644
--- a/core/fxcrt/fx_coordinates.cpp
+++ b/core/fxcrt/fx_coordinates.cpp
@@ -43,6 +43,15 @@ static_assert(sizeof(FX_RECT::bottom) == sizeof(RECT::bottom),
               "FX_RECT vs. RECT mismatch");
 #endif
 
+inline CFX_Matrix ConcatInternal(const CFX_Matrix& left,
+                                 const CFX_Matrix& right) {
+  return CFX_Matrix(
+      left.a * right.a + left.b * right.c, left.a * right.b + left.b * right.d,
+      left.c * right.a + left.d * right.c, left.c * right.b + left.d * right.d,
+      left.e * right.a + left.f * right.c + right.e,
+      left.e * right.b + left.f * right.d + right.f);
+}
+
 }  // namespace
 
 void FX_RECT::Normalize() {
@@ -248,12 +257,20 @@ CFX_Matrix CFX_Matrix::GetInverse() const {
   return inverse;
 }
 
-void CFX_Matrix::Concat(const CFX_Matrix& m, bool bPrepended) {
-  ConcatInternal(m, bPrepended);
+void CFX_Matrix::Concat(const CFX_Matrix& m) {
+  *this = ConcatInternal(*this, m);
+}
+
+void CFX_Matrix::ConcatPrepend(const CFX_Matrix& m) {
+  *this = ConcatInternal(m, *this);
+}
+
+void CFX_Matrix::ConcatInverse(const CFX_Matrix& src) {
+  Concat(src.GetInverse());
 }
 
-void CFX_Matrix::ConcatInverse(const CFX_Matrix& src, bool bPrepended) {
-  Concat(src.GetInverse(), bPrepended);
+void CFX_Matrix::ConcatInversePrepend(const CFX_Matrix& src) {
+  ConcatPrepend(src.GetInverse());
 }
 
 bool CFX_Matrix::Is90Rotated() const {
@@ -264,47 +281,33 @@ bool CFX_Matrix::IsScaled() const {
   return fabs(b * 1000) < fabs(a) && fabs(c * 1000) < fabs(d);
 }
 
-void CFX_Matrix::Translate(float x, float y, bool bPrepended) {
-  if (bPrepended) {
-    e += x * a + y * c;
-    f += y * d + x * b;
-    return;
-  }
+void CFX_Matrix::Translate(float x, float y) {
   e += x;
   f += y;
 }
 
-void CFX_Matrix::Scale(float sx, float sy, bool bPrepended) {
-  a *= sx;
-  d *= sy;
-  if (bPrepended) {
-    b *= sx;
-    c *= sy;
-    return;
-  }
+void CFX_Matrix::TranslatePrepend(float x, float y) {
+  e += x * a + y * c;
+  f += y * d + x * b;
+}
 
+void CFX_Matrix::Scale(float sx, float sy) {
+  a *= sx;
   b *= sy;
   c *= sx;
+  d *= sy;
   e *= sx;
   f *= sy;
 }
 
-void CFX_Matrix::Rotate(float fRadian, bool bPrepended) {
+void CFX_Matrix::Rotate(float fRadian) {
   float cosValue = cos(fRadian);
   float sinValue = sin(fRadian);
-  ConcatInternal(CFX_Matrix(cosValue, sinValue, -sinValue, cosValue, 0, 0),
-                 bPrepended);
-}
-
-void CFX_Matrix::RotateAt(float fRadian, float x, float y, bool bPrepended) {
-  Translate(-x, -y, bPrepended);
-  Rotate(fRadian, bPrepended);
-  Translate(x, y, bPrepended);
+  Concat(CFX_Matrix(cosValue, sinValue, -sinValue, cosValue, 0, 0));
 }
 
-void CFX_Matrix::Shear(float fAlphaRadian, float fBetaRadian, bool bPrepended) {
-  ConcatInternal(CFX_Matrix(1, tan(fAlphaRadian), tan(fBetaRadian), 1, 0, 0),
-                 bPrepended);
+void CFX_Matrix::Shear(float fAlphaRadian, float fBetaRadian) {
+  Concat(CFX_Matrix(1, tan(fAlphaRadian), tan(fBetaRadian), 1, 0, 0));
 }
 
 void CFX_Matrix::MatchRect(const CFX_FloatRect& dest,
@@ -396,22 +399,3 @@ CFX_FloatRect CFX_Matrix::TransformRect(const CFX_FloatRect& rect) const {
       TransformRect(rect.left, rect.right, rect.top, rect.bottom);
   return CFX_FloatRect(left, bottom, right, top);
 }
-
-void CFX_Matrix::ConcatInternal(const CFX_Matrix& other, bool prepend) {
-  CFX_Matrix left;
-  CFX_Matrix right;
-  if (prepend) {
-    left = other;
-    right = *this;
-  } else {
-    left = *this;
-    right = other;
-  }
-
-  a = left.a * right.a + left.b * right.c;
-  b = left.a * right.b + left.b * right.d;
-  c = left.c * right.a + left.d * right.c;
-  d = left.c * right.b + left.d * right.d;
-  e = left.e * right.a + left.f * right.c + right.e;
-  f = left.e * right.b + left.f * right.d + right.f;
-}
diff --git a/core/fxcrt/fx_coordinates.h b/core/fxcrt/fx_coordinates.h
index 0b98ff2e43..f84c5ee220 100644
--- a/core/fxcrt/fx_coordinates.h
+++ b/core/fxcrt/fx_coordinates.h
@@ -592,8 +592,10 @@ class CFX_Matrix {
 
   CFX_Matrix GetInverse() const;
 
-  void Concat(const CFX_Matrix& m, bool bPrepended = false);
-  void ConcatInverse(const CFX_Matrix& m, bool bPrepended = false);
+  void Concat(const CFX_Matrix& right);
+  void ConcatPrepend(const CFX_Matrix& left);
+  void ConcatInverse(const CFX_Matrix& m);
+  void ConcatInversePrepend(const CFX_Matrix& m);
 
   bool IsIdentity() const {
     return a == 1 && b == 0 && c == 0 && d == 1 && e == 0 && f == 0;
@@ -603,18 +605,18 @@ class CFX_Matrix {
   bool IsScaled() const;
   bool WillScale() const { return a != 1.0f || b != 0 || c != 0 || d != 1.0f; }
 
-  void Translate(float x, float y, bool bPrepended = false);
-  void Translate(int32_t x, int32_t y, bool bPrepended = false) {
-    Translate(static_cast<float>(x), static_cast<float>(y), bPrepended);
+  void Translate(float x, float y);
+  void TranslatePrepend(float x, float y);
+  void Translate(int32_t x, int32_t y) {
+    Translate(static_cast<float>(x), static_cast<float>(y));
+  }
+  void TranslatePrepend(int32_t x, int32_t y) {
+    TranslatePrepend(static_cast<float>(x), static_cast<float>(y));
   }
 
-  void Scale(float sx, float sy, bool bPrepended = false);
-  void Rotate(float fRadian, bool bPrepended = false);
-
-  // Rotates counterclockwise around the (x, y) point.
-  void RotateAt(float fRadian, float x, float y, bool bPrepended = false);
-
-  void Shear(float fAlphaRadian, float fBetaRadian, bool bPrepended = false);
+  void Scale(float sx, float sy);
+  void Rotate(float fRadian);
+  void Shear(float fAlphaRadian, float fBetaRadian);
 
   void MatchRect(const CFX_FloatRect& dest, const CFX_FloatRect& src);
 
@@ -641,9 +643,6 @@ class CFX_Matrix {
   float d;
   float e;
   float f;
-
- private:
-  void ConcatInternal(const CFX_Matrix& other, bool prepend);
 };
 
 #endif  // CORE_FXCRT_FX_COORDINATES_H_
diff --git a/core/fxcrt/fx_coordinates_unittest.cpp b/core/fxcrt/fx_coordinates_unittest.cpp
index d77fe05e91..b885d07095 100644
--- a/core/fxcrt/fx_coordinates_unittest.cpp
+++ b/core/fxcrt/fx_coordinates_unittest.cpp
@@ -437,9 +437,9 @@ TEST(CFX_Matrix, ComposeTransformations) {
 
   // Now compose all transforms prepending.
   m.SetIdentity();
-  m.Concat(rotate_90, true);
-  m.Concat(translate_23_11, true);
-  m.Concat(scale_5_13, true);
+  m.ConcatPrepend(rotate_90);
+  m.ConcatPrepend(translate_23_11);
+  m.ConcatPrepend(scale_5_13);
   EXPECT_NEAR_FIVE_PLACES(0.0f, m.a);
   EXPECT_NEAR_FIVE_PLACES(5.0f, m.b);
   EXPECT_NEAR_FIVE_PLACES(-13.0f, m.c);
@@ -458,67 +458,3 @@ TEST(CFX_Matrix, ComposeTransformations) {
   EXPECT_FLOAT_EQ(-271.0f, p_10_20_transformed.x);
   EXPECT_FLOAT_EQ(73.0f, p_10_20_transformed.y);
 }
-
-TEST(CFX_Matrix, RotateAt) {
-  CFX_Matrix m;
-  m.RotateAt(FX_PI, 10, 20);
-
-  // 180 degree rotation
-  CFX_PointF p(27, 19);
-  CFX_PointF new_p = m.Transform(p);
-  EXPECT_FLOAT_EQ(-7, new_p.x);
-  EXPECT_FLOAT_EQ(21, new_p.y);
-
-  p = CFX_PointF(10, 20);
-  new_p = m.Transform(p);
-  EXPECT_FLOAT_EQ(10, new_p.x);
-  EXPECT_FLOAT_EQ(20, new_p.y);
-
-  p = CFX_PointF(0, 0);
-  new_p = m.Transform(p);
-  EXPECT_FLOAT_EQ(20, new_p.x);
-  EXPECT_FLOAT_EQ(40, new_p.y);
-
-  // 90 degree rotation
-  m.SetIdentity();
-  m.RotateAt(FX_PI / 2, 10, 20);
-
-  p = CFX_PointF(6, 17);
-  new_p = m.Transform(p);
-  EXPECT_FLOAT_EQ(13, new_p.x);
-  EXPECT_FLOAT_EQ(16, new_p.y);
-
-  p = CFX_PointF(10, 20);
-  new_p = m.Transform(p);
-  EXPECT_FLOAT_EQ(10, new_p.x);
-  EXPECT_FLOAT_EQ(20, new_p.y);
-
-  p = CFX_PointF(0, 0);
-  new_p = m.Transform(p);
-  EXPECT_FLOAT_EQ(30, new_p.x);
-  EXPECT_FLOAT_EQ(10, new_p.y);
-
-  // 60 degree rotation
-  m.SetIdentity();
-  m.RotateAt(FX_PI / 3, 10, 20);
-
-  p = CFX_PointF(20, 20);
-  new_p = m.Transform(p);
-  EXPECT_FLOAT_EQ(15, new_p.x);
-  EXPECT_FLOAT_EQ(28.660254f, new_p.y);
-
-  p = CFX_PointF(10, 20);
-  new_p = m.Transform(p);
-  EXPECT_FLOAT_EQ(10, new_p.x);
-  EXPECT_FLOAT_EQ(20, new_p.y);
-
-  p = CFX_PointF(0, 0);
-  new_p = m.Transform(p);
-  EXPECT_FLOAT_EQ(22.320509f, new_p.x);
-  EXPECT_FLOAT_EQ(1.3397465f, new_p.y);
-
-  p = CFX_PointF(10, -80);
-  new_p = m.Transform(p);
-  EXPECT_FLOAT_EQ(96.602540f, new_p.x);
-  EXPECT_FLOAT_EQ(-30, new_p.y);
-}
diff --git a/xfa/fwl/cfwl_widget.cpp b/xfa/fwl/cfwl_widget.cpp
index d0dbab10d5..4a8f2c0caa 100644
--- a/xfa/fwl/cfwl_widget.cpp
+++ b/xfa/fwl/cfwl_widget.cpp
@@ -191,12 +191,12 @@ CFX_Matrix CFWL_Widget::GetMatrix() {
     if (parent->m_pProperties)
       ctmOnParent.SetIdentity();
     rect = parent->GetWidgetRect();
-    matrix.Concat(ctmOnParent, true);
-    matrix.Translate(rect.left, rect.top, true);
+    matrix.ConcatPrepend(ctmOnParent);
+    matrix.TranslatePrepend(rect.left, rect.top);
   }
   CFX_Matrix m;
   m.SetIdentity();
-  matrix.Concat(m, true);
+  matrix.ConcatPrepend(m);
   parents.clear();
   return matrix;
 }
@@ -386,7 +386,7 @@ void CFWL_Widget::DrawBackground(CXFA_Graphics* pGraphics,
   param.m_iPart = iPartBk;
   param.m_pGraphics = pGraphics;
   if (pMatrix)
-    param.m_matrix.Concat(*pMatrix, true);
+    param.m_matrix.ConcatPrepend(*pMatrix);
   param.m_rtPart = GetRelativeRect();
   pTheme->DrawBackground(&param);
 }
@@ -399,7 +399,7 @@ void CFWL_Widget::DrawBorder(CXFA_Graphics* pGraphics,
   param.m_pWidget = this;
   param.m_iPart = iPartBorder;
   param.m_pGraphics = pGraphics;
-  param.m_matrix.Concat(matrix, true);
+  param.m_matrix.ConcatPrepend(matrix);
   param.m_rtPart = GetRelativeRect();
   pTheme->DrawBackground(&param);
 }
diff --git a/xfa/fwl/cfwl_widgetmgr.cpp b/xfa/fwl/cfwl_widgetmgr.cpp
index adbc895cff..42c972df98 100644
--- a/xfa/fwl/cfwl_widgetmgr.cpp
+++ b/xfa/fwl/cfwl_widgetmgr.cpp
@@ -424,7 +424,7 @@ void CFWL_WidgetMgr::DrawChild(CFWL_Widget* parent,
     if (pMatrix)
       widgetMatrix.Concat(*pMatrix);
 
-    widgetMatrix.Translate(rtWidget.left, rtWidget.top, true);
+    widgetMatrix.TranslatePrepend(rtWidget.left, rtWidget.top);
 
     if (IFWL_WidgetDelegate* pDelegate = child->GetDelegate())
       pDelegate->OnDrawWidget(pGraphics, widgetMatrix);