1 files changed, 151 insertions, 0 deletions
diff --git a/examples/quick/scenegraph/graph/linenode.cpp b/examples/quick/scenegraph/graph/linenode.cpp
new file mode 100644
index 0000000000..0d1229cf1d
--- /dev/null
+++ b/examples/quick/scenegraph/graph/linenode.cpp
@@ -0,0 +1,151 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** You may use this file under the terms of the BSD license as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names
+**     of its contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "linenode.h"
+
+#include <QtCore/QResource>
+
+#include <QtGui/QColor>
+
+#include <QtQuick/QSGSimpleMaterial>
+
+struct LineMaterial
+{
+    QColor color;
+    float spread;
+    float size;
+};
+
+class LineShader : public QSGSimpleMaterialShader<LineMaterial>
+{
+    QSG_DECLARE_SIMPLE_SHADER(LineShader, LineMaterial)
+
+public:
+    const char *vertexShader() const {
+        QResource r(":/scenegraph/graph/shaders/line.vsh");
+        Q_ASSERT(r.isValid());
+        return (const char *) r.data();
+    }
+
+    const char *fragmentShader() const {
+        QResource r(":/scenegraph/graph/shaders/line.fsh");
+        Q_ASSERT(r.isValid());
+        return (const char *) r.data();
+    }
+
+    QList<QByteArray> attributes() const {  return QList<QByteArray>() << "pos" << "t"; }
+
+    void updateState(const LineMaterial *m, const LineMaterial *) {
+        program()->setUniformValue(id_color, m->color);
+        program()->setUniformValue(id_spread, m->spread);
+        program()->setUniformValue(id_size, m->size);
+    }
+
+    void resolveUniforms() {
+        id_spread = program()->uniformLocation("spread");
+        id_size = program()->uniformLocation("size");
+        id_color = program()->uniformLocation("color");
+    }
+
+private:
+    int id_color;
+    int id_spread;
+    int id_size;
+};
+
+struct LineVertex {
+    float x;
+    float y;
+    float t;
+    inline void set(float xx, float yy, float tt) { x = xx; y = yy; t = tt; }
+};
+
+static const QSGGeometry::AttributeSet &attributes()
+{
+    static QSGGeometry::Attribute attr[] = {
+        QSGGeometry::Attribute::create(0, 2, GL_FLOAT, true),
+        QSGGeometry::Attribute::create(1, 1, GL_FLOAT)
+    };
+    static QSGGeometry::AttributeSet set = { 2, 3 * sizeof(float), attr };
+    return set;
+}
+
+LineNode::LineNode(float size, float spread, const QColor &color)
+    : m_geometry(attributes(), 0)
+{
+    setGeometry(&m_geometry);
+    m_geometry.setDrawingMode(GL_TRIANGLE_STRIP);
+
+    QSGSimpleMaterial<LineMaterial> *m = LineShader::createMaterial();
+    m->state()->color = color;
+    m->state()->size = size;
+    m->state()->spread = spread;
+    m->setFlag(QSGMaterial::Blending);
+    setMaterial(m);
+    setFlag(OwnsMaterial);
+}
+
+/*
+ * Assumes that samples have values in the range of 0 to 1 and scales them to
+ * the height of bounds. The samples are stretched out horizontally along the
+ * width of the bounds.
+ *
+ * The position of each pair of points is identical, but we use the third value
+ * "t" to shift the point up or down and to add antialiasing.
+ */
+void LineNode::updateGeometry(const QRectF &bounds, const QList<qreal> &samples)
+{
+    m_geometry.allocate(samples.size() * 2);
+
+    float x = bounds.x();
+    float y = bounds.y();
+    float w = bounds.width();
+    float h = bounds.height();
+
+    float dx = w / (samples.size() - 1);
+
+    LineVertex *v = (LineVertex *) m_geometry.vertexData();
+    for (int i=0; i<samples.size(); ++i) {
+        v[i*2+0].set(x + dx * i, y + samples.at(i) * h, 0);
+        v[i*2+1].set(x + dx * i, y + samples.at(i) * h, 1);
+    }
+
+    markDirty(QSGNode::DirtyGeometry);
+}