Enable the scenegraph to remove its QMatrix4x4_Accessor hack

Expose flagBits via a public function marked as internal.

Task-number: QTBUG-82670
Change-Id: Ia64d934d3dda3e718357cf4e3c32866a613a4722
Reviewed-by: Andy Nichols <andy.nichols@qt.io>
Reviewed-by: Christian Strømme <christian.stromme@qt.io>

2 files changed, 29 insertions, 5 deletions

diff --git a/src/gui/math3d/qmatrix4x4.cpp b/src/gui/math3d/qmatrix4x4.cpp
index 2adb94573b..2f7931d099 100644
--- a/src/gui/math3d/qmatrix4x4.cpp
+++ b/src/gui/math3d/qmatrix4x4.cpp
@@ -1280,6 +1280,23 @@ void QMatrix4x4::projectedRotate(float angle, float x, float y, float z)
     *this *= rot;
 }
 
+/*!
+    \fn int QMatrix4x4::flags() const
+    \internal
+*/
+
+/*!
+    \enum QMatrix4x4::Flags
+    \internal
+    \omitvalue Identity
+    \omitvalue Translation
+    \omitvalue Scale
+    \omitvalue Rotation2D
+    \omitvalue Rotation
+    \omitvalue Perspective
+    \omitvalue General
+*/
+
 #ifndef QT_NO_QUATERNION
 
 /*!
diff --git a/src/gui/math3d/qmatrix4x4.h b/src/gui/math3d/qmatrix4x4.h
index 95f4db92ec..64bf9c607e 100644
--- a/src/gui/math3d/qmatrix4x4.h
+++ b/src/gui/math3d/qmatrix4x4.h
@@ -185,12 +185,10 @@ public:
 #endif
 
     void projectedRotate(float angle, float x, float y, float z);
-private:
-    float m[4][4];          // Column-major order to match OpenGL.
-    int flagBits;           // Flag bits from the enum below.
 
     // When matrices are multiplied, the flag bits are or-ed together.
-    enum {
+    // Note that the ordering of the bit values matters. (ident < t < s < r2d < r < p)
+    enum Flag {
         Identity        = 0x0000, // Identity matrix
         Translation     = 0x0001, // Contains a translation
         Scale           = 0x0002, // Contains a scale
@@ -199,6 +197,13 @@ private:
         Perspective     = 0x0010, // Last row is different from (0, 0, 0, 1)
         General         = 0x001f  // General matrix, unknown contents
     };
+    Q_DECLARE_FLAGS(Flags, Flag)
+
+    Flags flags() const { return flagBits; }
+
+private:
+    float m[4][4];          // Column-major order to match OpenGL.
+    Flags flagBits;
 
     // Construct without initializing identity matrix.
     explicit QMatrix4x4(int) { }
@@ -206,6 +211,8 @@ private:
     QMatrix4x4 orthonormalInverse() const;
 };
 
+Q_DECLARE_OPERATORS_FOR_FLAGS(QMatrix4x4::Flags)
+
 QT_WARNING_PUSH
 QT_WARNING_DISABLE_CLANG("-Wfloat-equal")
 QT_WARNING_DISABLE_GCC("-Wfloat-equal")
@@ -627,7 +634,7 @@ inline QMatrix4x4 operator-(const QMatrix4x4& m1, const QMatrix4x4& m2)
 
 inline QMatrix4x4 operator*(const QMatrix4x4& m1, const QMatrix4x4& m2)
 {
-    int flagBits = m1.flagBits | m2.flagBits;
+    QMatrix4x4::Flags flagBits = m1.flagBits | m2.flagBits;
     if (flagBits < QMatrix4x4::Rotation2D) {
         QMatrix4x4 m = m1;
         m.m[3][0] += m.m[0][0] * m2.m[3][0];