Video texture streaming support via external EGLImage textures

Created new StreamVideoNode & StreamVideoMaterial classes
for QSG renderer. These classes duplicate the logic of
chromium's direct renderer GLRenderer::DrawStreamVideoQuad.
Added support for new DrawQuad material in DelegatedFrameNode.
Added support for external textures in MailboxTexture.

Change-Id: If569b07dfef985f9833de7e64eeb3f952026bca4
Reviewed-by: Arvid Nilsson <anilsson@blackberry.com>
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>

1 files changed, 138 insertions, 0 deletions

diff --git a/src/core/stream_video_node.cpp b/src/core/stream_video_node.cpp
new file mode 100644
index 000000000..8f8723bd3
--- /dev/null
+++ b/src/core/stream_video_node.cpp
@@ -0,0 +1,138 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 "stream_video_node.h"
+
+#include <QtQuick/qsgtexture.h>
+
+class StreamVideoMaterialShader : public QSGMaterialShader
+{
+public:
+    virtual void updateState(const RenderState &state, QSGMaterial *newMaterial, QSGMaterial *oldMaterial);
+
+    virtual char const *const *attributeNames() const {
+        static const char *names[] = {
+            "a_position",
+            "a_texCoord",
+            0
+        };
+        return names;
+    }
+
+protected:
+    virtual const char *vertexShader() const {
+        // Keep in sync with cc::VertexShaderVideoTransform
+        const char *shader =
+        "attribute highp vec4 a_position;\n"
+        "attribute mediump vec2 a_texCoord;\n"
+        "uniform highp mat4 matrix;\n"
+        "varying mediump vec2 v_texCoord;\n"
+        "void main() {\n"
+        "  gl_Position = matrix * a_position;\n"
+        "  v_texCoord = a_texCoord;\n"
+        "}";
+        return shader;
+    }
+
+    virtual const char *fragmentShader() const {
+        // Keep in sync with cc::FragmentShaderOESImageExternal
+        static const char *shader =
+        "#extension GL_OES_EGL_image_external : require\n"
+        "varying mediump vec2 v_texCoord;\n"
+        "uniform samplerExternalOES s_texture;\n"
+        "void main() {\n"
+        "  vec4 texColor = texture2D(s_texture, v_texCoord);\n"
+        "  gl_FragColor = texColor;\n"
+        "}";
+        return shader;
+    }
+
+    virtual void initialize() {
+        m_id_matrix = program()->uniformLocation("matrix");
+        m_id_sTexture = program()->uniformLocation("s_texture");
+    }
+
+    int m_id_matrix;
+    int m_id_sTexture;
+};
+
+void StreamVideoMaterialShader::updateState(const RenderState &state, QSGMaterial *newMaterial, QSGMaterial *oldMaterial)
+{
+    Q_UNUSED(oldMaterial);
+
+    StreamVideoMaterial *mat = static_cast<StreamVideoMaterial *>(newMaterial);
+    program()->setUniformValue(m_id_sTexture, 0);
+
+    mat->m_texture->bind();
+
+    // TODO(mchishtie): handle state.opacity() when shader implements it
+    if (state.isMatrixDirty())
+        program()->setUniformValue(m_id_matrix, state.combinedMatrix());
+}
+
+StreamVideoMaterial::StreamVideoMaterial(QSGTexture *texture)
+    : m_texture(texture)
+{
+}
+
+QSGMaterialShader *StreamVideoMaterial::createShader() const
+{
+    return new StreamVideoMaterialShader;
+}
+
+int StreamVideoMaterial::compare(const QSGMaterial *other) const
+{
+    const StreamVideoMaterial *m = static_cast<const StreamVideoMaterial *>(other);
+    return (m_texture->textureId() - m->m_texture->textureId());
+}
+
+StreamVideoNode::StreamVideoNode(QSGTexture *texture)
+    : m_geometry(QSGGeometry::defaultAttributes_TexturedPoint2D(), 4)
+{
+    setGeometry(&m_geometry);
+    setFlag(QSGNode::OwnsMaterial);
+    m_material = new StreamVideoMaterial(texture);
+    setMaterial(m_material);
+}
+
+void StreamVideoNode::setRect(const QRectF &rect)
+{
+    QSGGeometry::updateTexturedRectGeometry(geometry(), rect, QRectF(0, 0, 1, 1));
+}