Remove QMatrix4x4& return values in response to API review feedback

Reviewed-by: Sarah Smith

3 files changed, 65 insertions, 80 deletions

diff --git a/src/gui/math3d/qmatrix4x4.cpp b/src/gui/math3d/qmatrix4x4.cpp
index ef2e4ab..2c3d616 100644
--- a/src/gui/math3d/qmatrix4x4.cpp
+++ b/src/gui/math3d/qmatrix4x4.cpp
@@ -694,11 +694,11 @@ QMatrix4x4 operator/(const QMatrix4x4& matrix, qreal divisor)
 
 /*!
     Multiplies this matrix by another that scales coordinates by
-    the components of \a vector.  Returns this matrix.
+    the components of \a vector.
 
     \sa translate(), rotate()
 */
-QMatrix4x4& QMatrix4x4::scale(const QVector3D& vector)
+void QMatrix4x4::scale(const QVector3D& vector)
 {
     qreal vx = vector.x();
     qreal vy = vector.y();
@@ -732,7 +732,6 @@ QMatrix4x4& QMatrix4x4::scale(const QVector3D& vector)
         m[2][3] *= vz;
         flagBits = General;
     }
-    return *this;
 }
 #endif
 
@@ -740,11 +739,11 @@ QMatrix4x4& QMatrix4x4::scale(const QVector3D& vector)
     \overload
 
     Multiplies this matrix by another that scales coordinates by the
-    components \a x, and \a y.  Returns this matrix.
+    components \a x, and \a y.
 
     \sa translate(), rotate()
 */
-QMatrix4x4& QMatrix4x4::scale(qreal x, qreal y)
+void QMatrix4x4::scale(qreal x, qreal y)
 {
     if (flagBits == Identity) {
         m[0][0] = x;
@@ -768,18 +767,17 @@ QMatrix4x4& QMatrix4x4::scale(qreal x, qreal y)
         m[1][3] *= y;
         flagBits = General;
     }
-    return *this;
 }
 
 /*!
     \overload
 
     Multiplies this matrix by another that scales coordinates by the
-    components \a x, \a y, and \a z.  Returns this matrix.
+    components \a x, \a y, and \a z.
 
     \sa translate(), rotate()
 */
-QMatrix4x4& QMatrix4x4::scale(qreal x, qreal y, qreal z)
+void QMatrix4x4::scale(qreal x, qreal y, qreal z)
 {
     if (flagBits == Identity) {
         m[0][0] = x;
@@ -810,18 +808,17 @@ QMatrix4x4& QMatrix4x4::scale(qreal x, qreal y, qreal z)
         m[2][3] *= z;
         flagBits = General;
     }
-    return *this;
 }
 
 /*!
     \overload
 
     Multiplies this matrix by another that scales coordinates by the
-    given \a factor.  Returns this matrix.
+    given \a factor.
 
     \sa translate(), rotate()
 */
-QMatrix4x4& QMatrix4x4::scale(qreal factor)
+void QMatrix4x4::scale(qreal factor)
 {
     if (flagBits == Identity) {
         m[0][0] = factor;
@@ -852,17 +849,16 @@ QMatrix4x4& QMatrix4x4::scale(qreal factor)
         m[2][3] *= factor;
         flagBits = General;
     }
-    return *this;
 }
 
 #ifndef QT_NO_VECTOR3D
 /*!
     Multiplies this matrix by another that translates coordinates by
-    the components of \a vector.  Returns this matrix.
+    the components of \a vector.
 
     \sa scale(), rotate()
 */
-QMatrix4x4& QMatrix4x4::translate(const QVector3D& vector)
+void QMatrix4x4::translate(const QVector3D& vector)
 {
     qreal vx = vector.x();
     qreal vy = vector.y();
@@ -895,7 +891,6 @@ QMatrix4x4& QMatrix4x4::translate(const QVector3D& vector)
         else if (flagBits != (Rotation | Translation))
             flagBits = General;
     }
-    return *this;
 }
 
 #endif
@@ -904,11 +899,11 @@ QMatrix4x4& QMatrix4x4::translate(const QVector3D& vector)
     \overload
 
     Multiplies this matrix by another that translates coordinates
-    by the components \a x, and \a y.  Returns this matrix.
+    by the components \a x, and \a y.
 
     \sa scale(), rotate()
 */
-QMatrix4x4& QMatrix4x4::translate(qreal x, qreal y)
+void QMatrix4x4::translate(qreal x, qreal y)
 {
     if (flagBits == Identity) {
         m[3][0] = x;
@@ -935,18 +930,17 @@ QMatrix4x4& QMatrix4x4::translate(qreal x, qreal y)
         else if (flagBits != (Rotation | Translation))
             flagBits = General;
     }
-    return *this;
 }
 
 /*!
     \overload
 
     Multiplies this matrix by another that translates coordinates
-    by the components \a x, \a y, and \a z.  Returns this matrix.
+    by the components \a x, \a y, and \a z.
 
     \sa scale(), rotate()
 */
-QMatrix4x4& QMatrix4x4::translate(qreal x, qreal y, qreal z)
+void QMatrix4x4::translate(qreal x, qreal y, qreal z)
 {
     if (flagBits == Identity) {
         m[3][0] = x;
@@ -976,20 +970,19 @@ QMatrix4x4& QMatrix4x4::translate(qreal x, qreal y, qreal z)
         else if (flagBits != (Rotation | Translation))
             flagBits = General;
     }
-    return *this;
 }
 
 #ifndef QT_NO_VECTOR3D
 
 /*!
     Multiples this matrix by another that rotates coordinates through
-    \a angle degrees about \a vector.  Returns this matrix.
+    \a angle degrees about \a vector.
 
     \sa scale(), translate()
 */
-QMatrix4x4& QMatrix4x4::rotate(qreal angle, const QVector3D& vector)
+void QMatrix4x4::rotate(qreal angle, const QVector3D& vector)
 {
-    return rotate(angle, vector.x(), vector.y(), vector.z());
+    rotate(angle, vector.x(), vector.y(), vector.z());
 }
 
 #endif
@@ -998,14 +991,14 @@ QMatrix4x4& QMatrix4x4::rotate(qreal angle, const QVector3D& vector)
     \overload
 
     Multiplies this matrix by another that rotates coordinates through
-    \a angle degrees about the vector (\a x, \a y, \a z).  Returns this matrix.
+    \a angle degrees about the vector (\a x, \a y, \a z).
 
     \sa scale(), translate()
 */
-QMatrix4x4& QMatrix4x4::rotate(qreal angle, qreal x, qreal y, qreal z)
+void QMatrix4x4::rotate(qreal angle, qreal x, qreal y, qreal z)
 {
     if (angle == 0.0f)
-        return *this;
+        return;
     QMatrix4x4 m(1); // The "1" says to not load the identity.
     qreal c, s, ic;
     if (angle == 90.0f || angle == -270.0f) {
@@ -1102,18 +1095,17 @@ QMatrix4x4& QMatrix4x4::rotate(qreal angle, qreal x, qreal y, qreal z)
         flagBits = flags | Rotation;
     else
         flagBits = Rotation;
-    return *this;
 }
 
 /*!
     \internal
 */
-QMatrix4x4& QMatrix4x4::projectedRotate(qreal angle, qreal x, qreal y, qreal z)
+void QMatrix4x4::projectedRotate(qreal angle, qreal x, qreal y, qreal z)
 {
     // Used by QGraphicsRotation::applyTo() to perform a rotation
     // and projection back to 2D in a single step.
     if (angle == 0.0f)
-        return *this;
+        return;
     QMatrix4x4 m(1); // The "1" says to not load the identity.
     qreal c, s, ic;
     if (angle == 90.0f || angle == -270.0f) {
@@ -1206,7 +1198,6 @@ QMatrix4x4& QMatrix4x4::projectedRotate(qreal angle, qreal x, qreal y, qreal z)
         flagBits = flags | Rotation;
     else
         flagBits = Rotation;
-    return *this;
 }
 
 #ifndef QT_NO_QUATERNION
@@ -1214,11 +1205,11 @@ QMatrix4x4& QMatrix4x4::projectedRotate(qreal angle, qreal x, qreal y, qreal z)
 /*!
     Multiples this matrix by another that rotates coordinates according
     to a specified \a quaternion.  The \a quaternion is assumed to have
-    been normalized.  Returns this matrix.
+    been normalized.
 
     \sa scale(), translate(), QQuaternion
 */
-QMatrix4x4& QMatrix4x4::rotate(const QQuaternion& quaternion)
+void QMatrix4x4::rotate(const QQuaternion& quaternion)
 {
     // Algorithm from:
     // http://www.j3d.org/matrix_faq/matrfaq_latest.html#Q54
@@ -1254,7 +1245,6 @@ QMatrix4x4& QMatrix4x4::rotate(const QQuaternion& quaternion)
         flagBits = flags | Rotation;
     else
         flagBits = Rotation;
-    return *this;
 }
 
 #endif
@@ -1265,17 +1255,16 @@ QMatrix4x4& QMatrix4x4::rotate(const QQuaternion& quaternion)
     Multiplies this matrix by another that applies an orthographic
     projection for a window with boundaries specified by \a rect.
     The near and far clipping planes will be -1 and 1 respectively.
-    Returns this matrix.
 
     \sa frustum(), perspective()
 */
-QMatrix4x4& QMatrix4x4::ortho(const QRect& rect)
+void QMatrix4x4::ortho(const QRect& rect)
 {
     // Note: rect.right() and rect.bottom() subtract 1 in QRect,
     // which gives the location of a pixel within the rectangle,
     // instead of the extent of the rectangle.  We want the extent.
     // QRectF expresses the extent properly.
-    return ortho(rect.x(), rect.x() + rect.width(), rect.y() + rect.height(), rect.y(), -1.0f, 1.0f);
+    ortho(rect.x(), rect.x() + rect.width(), rect.y() + rect.height(), rect.y(), -1.0f, 1.0f);
 }
 
 /*!
@@ -1284,28 +1273,27 @@ QMatrix4x4& QMatrix4x4::ortho(const QRect& rect)
     Multiplies this matrix by another that applies an orthographic
     projection for a window with boundaries specified by \a rect.
     The near and far clipping planes will be -1 and 1 respectively.
-    Returns this matrix.
 
     \sa frustum(), perspective()
 */
-QMatrix4x4& QMatrix4x4::ortho(const QRectF& rect)
+void QMatrix4x4::ortho(const QRectF& rect)
 {
-    return ortho(rect.left(), rect.right(), rect.bottom(), rect.top(), -1.0f, 1.0f);
+    ortho(rect.left(), rect.right(), rect.bottom(), rect.top(), -1.0f, 1.0f);
 }
 
 /*!
     Multiplies this matrix by another that applies an orthographic
     projection for a window with lower-left corner (\a left, \a bottom),
     upper-right corner (\a right, \a top), and the specified \a nearPlane
-    and \a farPlane clipping planes.  Returns this matrix.
+    and \a farPlane clipping planes.
 
     \sa frustum(), perspective()
 */
-QMatrix4x4& QMatrix4x4::ortho(qreal left, qreal right, qreal bottom, qreal top, qreal nearPlane, qreal farPlane)
+void QMatrix4x4::ortho(qreal left, qreal right, qreal bottom, qreal top, qreal nearPlane, qreal farPlane)
 {
     // Bail out if the projection volume is zero-sized.
     if (left == right || bottom == top || nearPlane == farPlane)
-        return *this;
+        return;
 
     // Construct the projection.
     qreal width = right - left;
@@ -1324,7 +1312,7 @@ QMatrix4x4& QMatrix4x4::ortho(qreal left, qreal right, qreal bottom, qreal top,
             (2.0f / width,
              2.0f / invheight,
              -1.0f));
-        return *this;
+        return;
     }
 #endif
     QMatrix4x4 m(1);
@@ -1347,22 +1335,22 @@ QMatrix4x4& QMatrix4x4::ortho(qreal left, qreal right, qreal bottom, qreal top,
 
     // Apply the projection.
     *this *= m;
-    return *this;
+    return;
 }
 
 /*!
     Multiplies this matrix by another that applies a perspective
     frustum projection for a window with lower-left corner (\a left, \a bottom),
     upper-right corner (\a right, \a top), and the specified \a nearPlane
-    and \a farPlane clipping planes.  Returns this matrix.
+    and \a farPlane clipping planes.
 
     \sa ortho(), perspective()
 */
-QMatrix4x4& QMatrix4x4::frustum(qreal left, qreal right, qreal bottom, qreal top, qreal nearPlane, qreal farPlane)
+void QMatrix4x4::frustum(qreal left, qreal right, qreal bottom, qreal top, qreal nearPlane, qreal farPlane)
 {
     // Bail out if the projection volume is zero-sized.
     if (left == right || bottom == top || nearPlane == farPlane)
-        return *this;
+        return;
 
     // Construct the projection.
     QMatrix4x4 m(1);
@@ -1388,7 +1376,6 @@ QMatrix4x4& QMatrix4x4::frustum(qreal left, qreal right, qreal bottom, qreal top
 
     // Apply the projection.
     *this *= m;
-    return *this;
 }
 
 /*!
@@ -1396,22 +1383,21 @@ QMatrix4x4& QMatrix4x4::frustum(qreal left, qreal right, qreal bottom, qreal top
     projection.  The field of view will be \a angle degrees within
     a window with a given \a aspect ratio.  The projection will
     have the specified \a nearPlane and \a farPlane clipping planes.
-    Returns this matrix.
 
     \sa ortho(), frustum()
 */
-QMatrix4x4& QMatrix4x4::perspective(qreal angle, qreal aspect, qreal nearPlane, qreal farPlane)
+void QMatrix4x4::perspective(qreal angle, qreal aspect, qreal nearPlane, qreal farPlane)
 {
     // Bail out if the projection volume is zero-sized.
     if (nearPlane == farPlane || aspect == 0.0f)
-        return *this;
+        return;
 
     // Construct the projection.
     QMatrix4x4 m(1);
     qreal radians = (angle / 2.0f) * M_PI / 180.0f;
     qreal sine = qSin(radians);
     if (sine == 0.0f)
-        return *this;
+        return;
     qreal cotan = qCos(radians) / sine;
     qreal clip = farPlane - nearPlane;
     m.m[0][0] = cotan / aspect;
@@ -1433,7 +1419,6 @@ QMatrix4x4& QMatrix4x4::perspective(qreal angle, qreal aspect, qreal nearPlane,
 
     // Apply the projection.
     *this *= m;
-    return *this;
 }
 
 #ifndef QT_NO_VECTOR3D
@@ -1443,9 +1428,8 @@ QMatrix4x4& QMatrix4x4::perspective(qreal angle, qreal aspect, qreal nearPlane,
     transformation.  The \a center value indicates the center of the
     view that the \a eye is looking at.  The \a up value indicates
     which direction should be considered up with respect to the \a eye.
-    Returns this matrix.
 */
-QMatrix4x4& QMatrix4x4::lookAt(const QVector3D& eye, const QVector3D& center, const QVector3D& up)
+void QMatrix4x4::lookAt(const QVector3D& eye, const QVector3D& center, const QVector3D& up)
 {
     QVector3D forward = (center - eye).normalized();
     QVector3D side = QVector3D::crossProduct(forward, up).normalized();
@@ -1471,7 +1455,7 @@ QMatrix4x4& QMatrix4x4::lookAt(const QVector3D& eye, const QVector3D& center, co
     m.m[3][3] = 1.0f;
 
     *this *= m;
-    return translate(-eye);
+    translate(-eye);
 }
 
 #endif
@@ -1480,11 +1464,11 @@ QMatrix4x4& QMatrix4x4::lookAt(const QVector3D& eye, const QVector3D& center, co
     Flips between right-handed and left-handed coordinate systems
     by multiplying the y and z co-ordinates by -1.  This is normally
     used to create a left-handed orthographic view without scaling
-    the viewport as ortho() does.  Returns this matrix.
+    the viewport as ortho() does.
 
     \sa ortho()
 */
-QMatrix4x4& QMatrix4x4::flipCoordinates()
+void QMatrix4x4::flipCoordinates()
 {
     if (flagBits == Scale || flagBits == (Scale | Translation)) {
         m[1][1] = -m[1][1];
@@ -1508,7 +1492,6 @@ QMatrix4x4& QMatrix4x4::flipCoordinates()
         m[2][3] = -m[2][3];
         flagBits = General;
     }
-    return *this;
 }
 
 /*!
diff --git a/src/gui/math3d/qmatrix4x4.h b/src/gui/math3d/qmatrix4x4.h
index daebf9d..4193bdc 100644
--- a/src/gui/math3d/qmatrix4x4.h
+++ b/src/gui/math3d/qmatrix4x4.h
@@ -127,29 +127,29 @@ public:
     friend inline bool qFuzzyCompare(const QMatrix4x4& m1, const QMatrix4x4& m2);
 
 #ifndef QT_NO_VECTOR3D
-    QMatrix4x4& scale(const QVector3D& vector);
-    QMatrix4x4& translate(const QVector3D& vector);
-    QMatrix4x4& rotate(qreal angle, const QVector3D& vector);
+    void scale(const QVector3D& vector);
+    void translate(const QVector3D& vector);
+    void rotate(qreal angle, const QVector3D& vector);
 #endif
-    QMatrix4x4& scale(qreal x, qreal y);
-    QMatrix4x4& scale(qreal x, qreal y, qreal z);
-    QMatrix4x4& scale(qreal factor);
-    QMatrix4x4& translate(qreal x, qreal y);
-    QMatrix4x4& translate(qreal x, qreal y, qreal z);
-    QMatrix4x4& rotate(qreal angle, qreal x, qreal y, qreal z = 0.0f);
+    void scale(qreal x, qreal y);
+    void scale(qreal x, qreal y, qreal z);
+    void scale(qreal factor);
+    void translate(qreal x, qreal y);
+    void translate(qreal x, qreal y, qreal z);
+    void rotate(qreal angle, qreal x, qreal y, qreal z = 0.0f);
 #ifndef QT_NO_QUATERNION
-    QMatrix4x4& rotate(const QQuaternion& quaternion);
+    void rotate(const QQuaternion& quaternion);
 #endif
 
-    QMatrix4x4& ortho(const QRect& rect);
-    QMatrix4x4& ortho(const QRectF& rect);
-    QMatrix4x4& ortho(qreal left, qreal right, qreal bottom, qreal top, qreal nearPlane, qreal farPlane);
-    QMatrix4x4& frustum(qreal left, qreal right, qreal bottom, qreal top, qreal nearPlane, qreal farPlane);
-    QMatrix4x4& perspective(qreal angle, qreal aspect, qreal nearPlane, qreal farPlane);
+    void ortho(const QRect& rect);
+    void ortho(const QRectF& rect);
+    void ortho(qreal left, qreal right, qreal bottom, qreal top, qreal nearPlane, qreal farPlane);
+    void frustum(qreal left, qreal right, qreal bottom, qreal top, qreal nearPlane, qreal farPlane);
+    void perspective(qreal angle, qreal aspect, qreal nearPlane, qreal farPlane);
 #ifndef QT_NO_VECTOR3D
-    QMatrix4x4& lookAt(const QVector3D& eye, const QVector3D& center, const QVector3D& up);
+    void lookAt(const QVector3D& eye, const QVector3D& center, const QVector3D& up);
 #endif
-    QMatrix4x4& flipCoordinates();
+    void flipCoordinates();
 
     void copyDataTo(qreal *values) const;
 
@@ -203,7 +203,7 @@ private:
 
     QMatrix4x4 orthonormalInverse() const;
 
-    QMatrix4x4& projectedRotate(qreal angle, qreal x, qreal y, qreal z);
+    void projectedRotate(qreal angle, qreal x, qreal y, qreal z);
 
     friend class QGraphicsRotation;
 };
diff --git a/tests/auto/qvariant/tst_qvariant.cpp b/tests/auto/qvariant/tst_qvariant.cpp
index e2a606f..3d68a73 100644
--- a/tests/auto/qvariant/tst_qvariant.cpp
+++ b/tests/auto/qvariant/tst_qvariant.cpp
@@ -1432,8 +1432,10 @@ void tst_QVariant::matrix4x4()
     QVariant variant;
     QMatrix4x4 matrix = qVariantValue<QMatrix4x4>(variant);
     QVERIFY(matrix.isIdentity());
-    qVariantSetValue(variant, QMatrix4x4().scale(2.0));
-    QCOMPARE(QMatrix4x4().scale(2.0), qVariantValue<QMatrix4x4>(variant));
+    QMatrix4x4 m;
+    m.scale(2.0f);
+    qVariantSetValue(variant, m);
+    QCOMPARE(m, qVariantValue<QMatrix4x4>(variant));
 
     void *mmatrix = QMetaType::construct(QVariant::Matrix4x4, 0);
     QVERIFY(mmatrix);