Tracing/QmlProfiler: Prepare for porting of shaders to Qt 6

This change touches up the shader handling code in Tracing and
QmlProfiler in order to pave the way for the pending porting of
the shaders to Qt 6.

- Use QSGGeometry::Attribute::createWithAttributeType instead of
  QSGGeometry::Attribute::create
- Undefine some fields that are unused in Qt 6
- Add a couple of comments to document the relation between C++
  variables and shader attributes
- Extract some code into functions

Change-Id: I0e7119484b6190a415a5c2d2a0bbd6465088cf19
Reviewed-by: Henning Gründl <[email protected]>

3 files changed, 48 insertions, 39 deletions

diff --git a/src/libs/tracing/timelineitemsrenderpass.cpp b/src/libs/tracing/timelineitemsrenderpass.cpp
index 9911382240a..344810d81d4 100644
--- a/src/libs/tracing/timelineitemsrenderpass.cpp
+++ b/src/libs/tracing/timelineitemsrenderpass.cpp
@@ -357,14 +357,22 @@ static qint64 endTime(const TimelineModel *model, const TimelineRenderState *par
 
 const QSGGeometry::AttributeSet &OpaqueColoredPoint2DWithSize::attributes()
 {
-    static QSGGeometry::Attribute data[] = {
-        QSGGeometry::Attribute::create(0, 2, QSGGeometry::FloatType, true),
-        QSGGeometry::Attribute::create(1, 2, QSGGeometry::FloatType),
-        QSGGeometry::Attribute::create(2, 1, QSGGeometry::FloatType),
-        QSGGeometry::Attribute::create(3, 4, QSGGeometry::UnsignedByteType)
+    static const QSGGeometry::Attribute data[] = {
+        // vec4 vertexCoord
+        QSGGeometry::Attribute::createWithAttributeType(0, 2, QSGGeometry::FloatType,
+                                                        QSGGeometry::PositionAttribute),
+        // vec2 rectSize
+        QSGGeometry::Attribute::createWithAttributeType(1, 2, QSGGeometry::FloatType,
+                                                        QSGGeometry::UnknownAttribute),
+        // float selectionId
+        QSGGeometry::Attribute::createWithAttributeType(2, 1, QSGGeometry::FloatType,
+                                                        QSGGeometry::UnknownAttribute),
+        // vec4 vertexColor
+        QSGGeometry::Attribute::createWithAttributeType(3, 4, QSGGeometry::UnsignedByteType,
+                                                        QSGGeometry::ColorAttribute),
     };
-    static QSGGeometry::AttributeSet attrs = {
-        4,
+    static const QSGGeometry::AttributeSet attrs = {
+        sizeof(data) / sizeof(data[0]),
         sizeof(OpaqueColoredPoint2DWithSize),
         data
     };
@@ -448,13 +456,13 @@ public:
 private:
 #if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
     void initialize() override;
-#endif // < Qt 6
 
     int m_matrix_id;
     int m_scale_id;
     int m_selection_color_id;
     int m_selected_item_id;
     int m_z_range_id;
+#endif // < Qt 6
 };
 
 TimelineItemsMaterialShader::TimelineItemsMaterialShader()
@@ -556,17 +564,12 @@ QSGMaterialType *TimelineItemsMaterial::type() const
 
 #if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
 QSGMaterialShader *TimelineItemsMaterial::createShader() const
-{
-    return new TimelineItemsMaterialShader;
-}
 #else // < Qt 6
-QSGMaterialShader *TimelineItemsMaterial::createShader(
-        QSGRendererInterface::RenderMode renderMode) const
+QSGMaterialShader *TimelineItemsMaterial::createShader(QSGRendererInterface::RenderMode) const
+#endif // < Qt 6
 {
-    Q_UNUSED(renderMode);
     return new TimelineItemsMaterialShader;
 }
-#endif // < Qt 6
 
 TimelineItemsRenderPassState::TimelineItemsRenderPassState(const TimelineModel *model) :
     m_indexFrom(std::numeric_limits<int>::max()), m_indexTo(-1)
diff --git a/src/libs/tracing/timelineitemsrenderpass.h b/src/libs/tracing/timelineitemsrenderpass.h
index 807f0ed5518..9d52be9ac71 100644
--- a/src/libs/tracing/timelineitemsrenderpass.h
+++ b/src/libs/tracing/timelineitemsrenderpass.h
@@ -48,7 +48,7 @@ public:
 #if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
     QSGMaterialShader *createShader() const override;
 #else
-    QSGMaterialShader *createShader(QSGRendererInterface::RenderMode renderMode) const override;
+    QSGMaterialShader *createShader(QSGRendererInterface::RenderMode) const override;
 #endif // < Qt 6
 
 private:
@@ -83,8 +83,10 @@ public:
     static OpaqueColoredPoint2DWithSize *fromVertexData(QSGGeometry *geometry);
 
 private:
-    float x, y, w, h, id;
-    unsigned char r, g, b, a;
+    float x, y; // vec4 vertexCoord
+    float w, h; // vec2 rectSize
+    float id; // float selectionId
+    unsigned char r, g, b, a; // vec4 vertexColor
 
     void setCommon(const OpaqueColoredPoint2DWithSize *master);
     void setLeft(const OpaqueColoredPoint2DWithSize *master);
diff --git a/src/libs/tracing/timelinenotesrenderpass.cpp b/src/libs/tracing/timelinenotesrenderpass.cpp
index 90a10ca4602..e71366e74eb 100644
--- a/src/libs/tracing/timelinenotesrenderpass.cpp
+++ b/src/libs/tracing/timelinenotesrenderpass.cpp
@@ -32,7 +32,8 @@
 namespace Timeline {
 
 struct Point2DWithDistanceFromTop {
-    float x, y, d;
+    float x, y; // vec4 vertexCoord
+    float d; // float distanceFromTop
     void set(float nx, float ny, float nd);
 };
 
@@ -43,7 +44,7 @@ public:
 #if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
     QSGMaterialShader *createShader() const final;
 #else // < Qt 6
-    QSGMaterialShader *createShader(QSGRendererInterface::RenderMode renderMode) const final;
+    QSGMaterialShader *createShader(QSGRendererInterface::RenderMode) const final;
 #endif // < Qt 6
 };
 
@@ -82,12 +83,16 @@ private:
 
 const QSGGeometry::AttributeSet &NotesGeometry::point2DWithDistanceFromTop()
 {
-    static QSGGeometry::Attribute data[] = {
-        QSGGeometry::Attribute::create(0, 2, QSGGeometry::FloatType, true),
-        QSGGeometry::Attribute::create(1, 1, QSGGeometry::FloatType),
+    static const QSGGeometry::Attribute data[] = {
+        // vec4 vertexCoord
+        QSGGeometry::Attribute::createWithAttributeType(0, 2, QSGGeometry::FloatType,
+                                                        QSGGeometry::PositionAttribute),
+        // float distanceFromTop
+        QSGGeometry::Attribute::createWithAttributeType(1, 1, QSGGeometry::FloatType,
+                                                        QSGGeometry::UnknownAttribute),
     };
-    static QSGGeometry::AttributeSet attrs = {
-        2,
+    static const QSGGeometry::AttributeSet attrs = {
+        sizeof(data) / sizeof(data[0]),
         sizeof(Point2DWithDistanceFromTop),
         data
     };
@@ -229,18 +234,17 @@ public:
                      QSGMaterial *oldEffect) override;
     char const *const *attributeNames() const override;
 #else // < Qt 6
-    bool updateUniformData(RenderState &state,
-                           QSGMaterial *newMaterial, QSGMaterial *oldMaterial) override;
+    bool updateUniformData(RenderState &state, QSGMaterial *, QSGMaterial *) override;
 #endif // < Qt 6
 
 private:
 #if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
     void initialize() override;
-#endif // < Qt 6
 
     int m_matrix_id;
     int m_z_range_id;
     int m_color_id;
+#endif // < Qt 6
 };
 
 NotesMaterialShader::NotesMaterialShader()
@@ -255,20 +259,24 @@ NotesMaterialShader::NotesMaterialShader()
 #endif // < Qt 6
 }
 
+static QColor notesColor()
+{
+    return Utils::creatorTheme()
+            ? Utils::creatorTheme()->color(Utils::Theme::Timeline_HighlightColor)
+            : QColor(255, 165, 0);
+}
+
 #if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
 void NotesMaterialShader::updateState(const RenderState &state, QSGMaterial *, QSGMaterial *)
 {
     if (state.isMatrixDirty()) {
         program()->setUniformValue(m_matrix_id, state.combinedMatrix());
         program()->setUniformValue(m_z_range_id, GLfloat(1.0));
-        const QColor notesColor = Utils::creatorTheme()
-                ? Utils::creatorTheme()->color(Utils::Theme::Timeline_HighlightColor)
-                : QColor(255, 165, 0);
-        program()->setUniformValue(m_color_id, notesColor);
+        program()->setUniformValue(m_color_id, notesColor());
     }
 }
 #else // < Qt 6
-bool NotesMaterialShader::updateUniformData(QSGMaterialShader::RenderState &state, QSGMaterial *, QSGMaterial *)
+bool NotesMaterialShader::updateUniformData(RenderState &state, QSGMaterial *, QSGMaterial *)
 {
     if (state.isMatrixDirty()) {
     }
@@ -299,16 +307,12 @@ QSGMaterialType *NotesMaterial::type() const
 
 #if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
 QSGMaterialShader *NotesMaterial::createShader() const
-{
-    return new NotesMaterialShader;
-}
 #else // < Qt 6
-QSGMaterialShader *NotesMaterial::createShader(QSGRendererInterface::RenderMode renderMode) const
+QSGMaterialShader *NotesMaterial::createShader(QSGRendererInterface::RenderMode) const
+#endif // < Qt 6
 {
-    Q_UNUSED(renderMode);
     return new NotesMaterialShader;
 }
-#endif // < Qt 6
 
 void Point2DWithDistanceFromTop::set(float nx, float ny, float nd)
 {