Added GL_POINTS for scatter

Task-number: QTRD-2535

Change-Id: Icf2d4ab1d8a46ea38864d2b587411ed05c58de38
Change-Id: Icf2d4ab1d8a46ea38864d2b587411ed05c58de38
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@digia.com>

1 files changed, 29 insertions, 1 deletions

diff --git a/src/datavisualization/engine/drawer.cpp b/src/datavisualization/engine/drawer.cpp
index 8643d6d9..93336e96 100644
--- a/src/datavisualization/engine/drawer.cpp
+++ b/src/datavisualization/engine/drawer.cpp
@@ -41,17 +41,22 @@ StaticLibInitializer staticLibInitializer;
 
 QT_DATAVISUALIZATION_BEGIN_NAMESPACE
 
+// Vertex array buffer for point
+const GLfloat point_data[] = {0.0f, 0.0f, 0.0f};
+
 Drawer::Drawer(const Theme &theme, const QFont &font, QDataVis::LabelStyle style)
     : m_theme(theme),
       m_font(font),
       m_style(style),
-      m_textureHelper(0)
+      m_textureHelper(0),
+      m_pointbuffer(0)
 {
 }
 
 Drawer::~Drawer()
 {
     delete m_textureHelper;
+    glDeleteBuffers(1, &m_pointbuffer);
 }
 
 void Drawer::initializeOpenGL()
@@ -163,6 +168,29 @@ void Drawer::drawSurfaceGrid(ShaderHelper *shader, SurfaceObject *object)
     glDisableVertexAttribArray(shader->posAtt());
 }
 
+void Drawer::drawPoint(ShaderHelper *shader)
+{
+    // Generate vertex buffer for point if it does not exist
+    if (!m_pointbuffer) {
+        glGenBuffers(1, &m_pointbuffer);
+        glBindBuffer(GL_ARRAY_BUFFER, m_pointbuffer);
+        glBufferData(GL_ARRAY_BUFFER, sizeof(point_data), point_data, GL_STATIC_DRAW);
+    }
+
+    // 1st attribute buffer : vertices
+    glEnableVertexAttribArray(shader->posAtt());
+    glBindBuffer(GL_ARRAY_BUFFER, m_pointbuffer);
+    glVertexAttribPointer(shader->posAtt(), 3, GL_FLOAT, GL_FALSE, 0, (void*)0);
+
+    // Draw the point
+    glDrawArrays(GL_POINTS, 0, 1);
+
+    // Free buffers
+    glBindBuffer(GL_ARRAY_BUFFER, 0);
+
+    glDisableVertexAttribArray(shader->posAtt());
+}
+
 void Drawer::drawLabel(const AbstractRenderItem &item, const LabelItem &labelItem,
                        const QMatrix4x4 &viewmatrix, const QMatrix4x4 &projectionmatrix,
                        const QVector3D &positionComp, const QVector3D &rotation,