Aspect ratio preservation for surface slice view

Task-number: QTRD-2387

Change-Id: I51e9900d419931e75d5df2f5962590ee5f3cdbc7
Reviewed-by: Tomi Korpipää <tomi.korpipaa@digia.com>
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@digia.com>
Reviewed-by: Pasi Keränen <pasi.keranen@digia.com>

2 files changed, 12 insertions, 19 deletions

diff --git a/src/datavisualization/engine/selectionpointer.cpp b/src/datavisualization/engine/selectionpointer.cpp
index d1a4c42a..6c3e0c8b 100644
--- a/src/datavisualization/engine/selectionpointer.cpp
+++ b/src/datavisualization/engine/selectionpointer.cpp
@@ -34,6 +34,8 @@
 
 QT_DATAVISUALIZATION_BEGIN_NAMESPACE
 
+const GLfloat sliceUnits = 2.5;
+
 SelectionPointer::SelectionPointer(Drawer *drawer)
     : QObject(0),
       m_labelShader(0),
@@ -102,11 +104,12 @@ void SelectionPointer::render(GLuint defaultFboHandle)
     QMatrix4x4 viewMatrix;
     QMatrix4x4 projectionMatrix;
     if (m_cachedIsSlicingActivated) {
-        GLfloat camZPosSliced = 5.0f / m_autoScaleAdjustment + zComp;
-        viewMatrix.lookAt(QVector3D(0.0f, 0.0f, camZPosSliced),
+        GLfloat aspect = (GLfloat)m_mainViewPort.width() / (GLfloat)m_mainViewPort.height();
+        viewMatrix.lookAt(QVector3D(0.0f, 0.0f, zComp + 1.0),
                           QVector3D(0.0f, 0.0f, zComp),
                           QVector3D(0.0f, 1.0f, 0.0f));
-        projectionMatrix.ortho(-3.0f, 3.0, -3.0, 3.0, 0.1f, 100.0f);
+        projectionMatrix.ortho(-sliceUnits * aspect, sliceUnits * aspect,
+                               -sliceUnits, sliceUnits, -1.0f, 14.0f);
     } else {
         viewMatrix = camera->viewMatrix();
         projectionMatrix.perspective(45.0f, (GLfloat)m_mainViewPort.width()
@@ -117,11 +120,6 @@ void SelectionPointer::render(GLuint defaultFboHandle)
     GLfloat scaledFontSize = 0.05f + m_drawer->font().pointSizeF() / 500.0f;
     GLfloat scaleFactor = scaledFontSize / (GLfloat)textureSize.height();
 
-    // Set up projection matrix
-//    QMatrix4x4 projectionMatrix;
-//    projectionMatrix.perspective(45.0f, (GLfloat)m_mainViewPort.width()
-//                                 / (GLfloat)m_mainViewPort.height(), 0.1f, 100.0f);
-
     QMatrix4x4 modelMatrix;
     QMatrix4x4 MVPMatrix;
 
diff --git a/src/datavisualization/engine/surface3drenderer.cpp b/src/datavisualization/engine/surface3drenderer.cpp
index fdefe7f0..5b771684 100644
--- a/src/datavisualization/engine/surface3drenderer.cpp
+++ b/src/datavisualization/engine/surface3drenderer.cpp
@@ -55,6 +55,7 @@ const GLfloat backgroundBottom = 1.0f;
 const GLfloat gridLineWidth = 0.005f;
 const GLfloat sliceZScale = 0.1f;
 const GLfloat surfaceGridYOffsetValue = 0.001f;
+const GLfloat sliceUnits = 2.5f;
 const int subViewDivider = 5;
 // The second offset to opposite direction is double because same matrix is translated twice
 const GLfloat surfaceGridYOffset[2] = {-surfaceGridYOffsetValue, 2.0f * surfaceGridYOffsetValue};
@@ -471,15 +472,14 @@ void Surface3DRenderer::drawSlicedScene()
 
     // Set up projection matrix
     QMatrix4x4 projectionMatrix;
-    projectionMatrix.ortho(-3.0f, 3.0, -3.0, 3.0, 0.1f, 100.0f);
+
+    GLfloat aspect = (GLfloat)m_mainViewPort.width() / (GLfloat)m_mainViewPort.height();
+    projectionMatrix.ortho(-sliceUnits * aspect, sliceUnits * aspect,
+                           -sliceUnits, sliceUnits, -1.0f, 14.0f); // 14.0 because of zComp
 
     // Set view matrix
     QMatrix4x4 viewMatrix;
-
-    // Adjust scaling (zoom rate based on aspect ratio)
-    GLfloat camZPosSliced = 5.0f / m_autoScaleAdjustment + zComp;
-
-    viewMatrix.lookAt(QVector3D(0.0f, 0.0f, camZPosSliced),
+    viewMatrix.lookAt(QVector3D(0.0f, 0.0f, zComp + 1.0f),
                       QVector3D(0.0f, 0.0f, zComp),
                       QVector3D(0.0f, 1.0f, 0.0f));
 
@@ -505,9 +505,6 @@ void Surface3DRenderer::drawSlicedScene()
         ShaderHelper *surfaceShader = m_shader;
         surfaceShader->bind();
 
-        // For surface we can see climpses from underneath
-        glDisable(GL_CULL_FACE);
-
         QMatrix4x4 modelMatrix;
         QMatrix4x4 MVPMatrix;
         QMatrix4x4 itModelMatrix;
@@ -540,8 +537,6 @@ void Surface3DRenderer::drawSlicedScene()
 
         surfaceShader->release();
 
-        glEnable(GL_CULL_FACE);
-
         // Draw surface grid
         if (m_cachedSurfaceGridOn) {
             m_surfaceGridShader->bind();