Replacing GL_QUADS and GL_POLYGON with triangles

This is necessary for building against OpenGL ES, and is also
generally just a Good Idea, as triangles are more friendly to
almost all graphics hardware.

Change-Id: Iabdec5d01a3a61c61990b39a6a94279c60a9731e
Reviewed-by: David Laing <david.laing@nokia.com>

2 files changed, 9 insertions, 6 deletions

diff --git a/src/imports/location/qdeclarativepolygonmapitem.cpp b/src/imports/location/qdeclarativepolygonmapitem.cpp
index d65f58a0..f3f510fa 100644
--- a/src/imports/location/qdeclarativepolygonmapitem.cpp
+++ b/src/imports/location/qdeclarativepolygonmapitem.cpp
@@ -273,7 +273,7 @@ MapPolygonNode::MapPolygonNode() :
     border_(new MapPolylineNode()),
     geometry_(QSGGeometry::defaultAttributes_Point2D(), 0)
 {
-    geometry_.setDrawingMode(GL_POLYGON);
+    geometry_.setDrawingMode(GL_TRIANGLE_FAN);
     QSGGeometryNode::setMaterial(&fill_material_);
     QSGGeometryNode::setGeometry(&geometry_);
 
@@ -296,13 +296,15 @@ void MapPolygonNode::update(const QColor& fillColor, const QPolygonF& shape,
 
     int fillVertexCount = 0;
     //note this will not allocate new buffer if the size has not changed
-    fill->allocate(shape.size());
+    fill->allocate(shape.size() + 2);
 
     Vertex *vertices = (Vertex *)fill->vertexData();
 
+    vertices[fillVertexCount++].position = QVector2D(shape.boundingRect().center());
     for (int i = 0; i < shape.size(); ++i) {
         vertices[fillVertexCount++].position = QVector2D(shape.at(i));
     }
+    vertices[fillVertexCount++].position = QVector2D(shape.at(0));
 
     Q_ASSERT(fillVertexCount == fill->vertexCount());
     markDirty(DirtyGeometry);
diff --git a/src/imports/location/qdeclarativerectanglemapitem.cpp b/src/imports/location/qdeclarativerectanglemapitem.cpp
index 94b301a0..0908c3a0 100644
--- a/src/imports/location/qdeclarativerectanglemapitem.cpp
+++ b/src/imports/location/qdeclarativerectanglemapitem.cpp
@@ -231,7 +231,7 @@ void QDeclarativeRectangleMapItem::dragStarted()
 MapRectangleNode::MapRectangleNode():
     geometry_(QSGGeometry::defaultAttributes_Point2D(),0)
 {
-    geometry_.setDrawingMode(GL_QUADS);
+    geometry_.setDrawingMode(GL_TRIANGLE_STRIP);
     QSGGeometryNode::setMaterial(&fillMaterial_);
     QSGGeometryNode::setGeometry(&geometry_);
 }
@@ -248,15 +248,16 @@ void MapRectangleNode::update(const QColor& fillColor, const QRectF& shape)
 
     int fillVertexCount = 0;
     //note this will not allocate new buffer if the size has not changed
-    fill->allocate(4);
+    fill->allocate(5);
 
     Vertex *vertices = (Vertex *)fill->vertexData();
 
     //set corners
-    vertices[fillVertexCount++].position = QVector2D(shape.left(),shape.top());
+    vertices[fillVertexCount++].position = QVector2D(shape.left(), shape.top());
     vertices[fillVertexCount++].position = QVector2D(shape.right(),shape.top());
     vertices[fillVertexCount++].position = QVector2D(shape.right(),shape.bottom());
-    vertices[fillVertexCount++].position = QVector2D(shape.left(),shape.bottom());
+    vertices[fillVertexCount++].position = QVector2D(shape.left(), shape.bottom());
+    vertices[fillVertexCount++].position = QVector2D(shape.left(), shape.top());
 
     Q_ASSERT(fillVertexCount == fill->vertexCount());