Object drawing and label generation moved to their own class

Change-Id: I3721b201dd83b471cb6d55f0dd7def908c4ab0be
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@digia.com>

1 files changed, 169 insertions, 0 deletions

diff --git a/src/datavis3d/engine/drawer.cpp b/src/datavis3d/engine/drawer.cpp
new file mode 100644
index 00000000..c33dd625
--- /dev/null
+++ b/src/datavis3d/engine/drawer.cpp
@@ -0,0 +1,169 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtDataVis3D module.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "drawer_p.h"
+#include "shaderhelper_p.h"
+#include "objecthelper_p.h"
+#include "qdataitem.h"
+#include "qdataitem_p.h"
+#include "utils_p.h"
+#include "texturehelper_p.h"
+
+QTCOMMERCIALDATAVIS3D_BEGIN_NAMESPACE
+
+Drawer::Drawer(const Theme &theme, const QFont &font, Q3DBars::LabelTransparency transparency)
+    : m_theme(theme),
+    m_font(font),
+    m_transparency(transparency),
+    m_textureHelper(new TextureHelper())
+{
+    initializeOpenGLFunctions();
+}
+
+Drawer::~Drawer()
+{
+
+}
+
+void Drawer::setTheme(const Theme &theme)
+{
+    m_theme = theme;
+}
+
+void Drawer::setFont(const QFont &font)
+{
+    m_font = font;
+}
+
+void Drawer::setTransparency(Q3DBars::LabelTransparency transparency)
+{
+    m_transparency = transparency;
+}
+
+void Drawer::drawObject(ShaderHelper *shader, ObjectHelper *object, bool textured,
+                        GLuint textureId)
+{
+    if (textured) {
+        // Activate texture
+        glActiveTexture(GL_TEXTURE0);
+        glBindTexture(GL_TEXTURE_2D, textureId);
+        shader->setUniformValue(shader->texture(), 0);
+    }
+
+    // 1st attribute buffer : vertices
+    glEnableVertexAttribArray(shader->posAtt());
+    glBindBuffer(GL_ARRAY_BUFFER, object->vertexBuf());
+    glVertexAttribPointer(shader->posAtt(), 3, GL_FLOAT, GL_FALSE, 0, (void*)0);
+
+    // 2nd attribute buffer : normals
+    glEnableVertexAttribArray(shader->normalAtt());
+    glBindBuffer(GL_ARRAY_BUFFER, object->normalBuf());
+    glVertexAttribPointer(shader->normalAtt(), 3, GL_FLOAT, GL_FALSE, 0, (void*)0);
+
+    if (textured) {
+        // 3rd attribute buffer : UVs
+        glEnableVertexAttribArray(shader->uvAtt());
+        glBindBuffer(GL_ARRAY_BUFFER, object->uvBuf());
+        glVertexAttribPointer(shader->uvAtt(), 2, GL_FLOAT, GL_FALSE, 0, (void*)0);
+    }
+
+    // Index buffer
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, object->elementBuf());
+
+    // Draw the triangles
+    glDrawElements(GL_TRIANGLES, object->indexCount(), GL_UNSIGNED_SHORT, (void*)0);
+
+    // Free buffers
+    glBindBuffer(GL_ARRAY_BUFFER, 0);
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
+
+    if (textured) {
+        glBindTexture(GL_TEXTURE_2D, 0);
+        glDisableVertexAttribArray(shader->uvAtt());
+    }
+    glDisableVertexAttribArray(shader->normalAtt());
+    glDisableVertexAttribArray(shader->posAtt());
+}
+
+void Drawer::generateLabelTexture(QDataItem *item)
+{
+    // Delete previous texture, if there is one
+    GLuint labelTexture = item->d_ptr->textureId();
+    if (labelTexture) {
+        // We have to do this, as we can't know if data is static or not;
+        // texture doesn't change with static data
+        // (basically we could create textures for all bars when data is added, but we
+        // may not need them -> better to do it here dynamically)
+        glDeleteTextures(1, &labelTexture);
+        item->d_ptr->setTextureId(0);
+    }
+
+    // Create labels
+    // Print label into a QImage using QPainter
+    QImage label = Utils::printTextToImage(m_font,
+                                           item->d_ptr->valueStr(),
+                                           m_theme.m_textBackgroundColor,
+                                           m_theme.m_textColor,
+                                           m_transparency);
+
+    // Set label size
+    item->d_ptr->setLabelSize(label.size());
+    // Insert text texture into label
+    item->d_ptr->setTextureId(m_textureHelper->create2DTexture(label, true, true));
+}
+
+GLuint Drawer::generateLabelTexture(const QString &text, QSize &labelSize)
+{
+    // Create labels
+    // Print label into a QImage using QPainter
+    QImage label = Utils::printTextToImage(m_font,
+                                           text,
+                                           m_theme.m_textBackgroundColor,
+                                           m_theme.m_textColor,
+                                           m_transparency);
+
+    // Set label size
+    labelSize = label.size();
+    // Insert text texture into label
+    return m_textureHelper->create2DTexture(label, true, true);
+}
+
+QTCOMMERCIALDATAVIS3D_END_NAMESPACE