Reuse existing GLTexture for equal LoadedTexture

Change-Id: I585b0f914ca02c12b3f8a0460ce2eb04e2861763
Reviewed-by: Andy Nichols <andy.nichols@qt.io>

9 files changed, 118 insertions, 6 deletions

diff --git a/src/runtime/dragon/dragon.pri b/src/runtime/dragon/dragon.pri
index 0f84f43..476269b 100644
--- a/src/runtime/dragon/dragon.pri
+++ b/src/runtime/dragon/dragon.pri
@@ -44,7 +44,8 @@ HEADERS += \
     $$PWD/dragonoptional_p.h \
     $$PWD/dragonstringtoint_p.h \
     $$PWD/dragonimmutable_p.h \
-    $$PWD/dragonmutable_p.h
+    $$PWD/dragonmutable_p.h \
+    $$PWD/dragoncomparegenerators_p.h
 
 SOURCES += \
     $$PWD/dragonattachmentpack.cpp \
diff --git a/src/runtime/dragon/dragoncomparegenerators_p.h b/src/runtime/dragon/dragoncomparegenerators_p.h
new file mode 100644
index 0000000..769ec3e
--- /dev/null
+++ b/src/runtime/dragon/dragoncomparegenerators_p.h
@@ -0,0 +1,72 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of Qt 3D Studio.
+**
+** $QT_BEGIN_LICENSE:GPL$
+** 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 The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 or (at your option) any later version
+** approved by the KDE Free Qt Foundation. The licenses are as published by
+** the Free Software Foundation and appearing in the file LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QT3DRENDER_DRAGON_COMPAREGENERATORS_P_H
+#define QT3DRENDER_DRAGON_COMPAREGENERATORS_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists for the convenience
+// of other Qt classes.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QSharedPointer>
+
+QT_BEGIN_NAMESPACE
+
+namespace Qt3DRender {
+namespace Dragon {
+
+/*! \internal
+ * Make sure two generators are equal by first checking if they are nullptr,
+ * then comparing them if they are not.
+ */
+template<typename T>
+bool compareGenerators(const QSharedPointer<T> &a, const QSharedPointer<T> &b)
+{
+    if (a == nullptr && b == nullptr)
+        return true;
+
+    if (a == nullptr || b == nullptr)
+        return false;
+
+    return *a == *b;
+}
+
+} // namespace Dragon
+} // namespace Qt3DRender
+
+QT_END_NAMESPACE
+
+#endif // QT3DRENDER_DRAGON_COMPAREGENERATORS_P_H
diff --git a/src/runtime/dragon/dragongltexture.cpp b/src/runtime/dragon/dragongltexture.cpp
index 48b9bb2..3bedd7f 100644
--- a/src/runtime/dragon/dragongltexture.cpp
+++ b/src/runtime/dragon/dragongltexture.cpp
@@ -128,7 +128,9 @@ GLTexture createGlTexture(const Immutable<LoadedTexture> &loadedTexture, QOpenGL
     if (loadedTexture->generator != nullptr || loadedTexture->images.size() > 0) {
         needUpload = true;
     }
+
     GLTexture result;
+    result.loadedTexture = loadedTexture;
     result.properties = deriveProperties(loadedTexture);
     result.parameters = loadedTexture->texture->parameters;
     result.actualTarget = loadedTexture->texture->properties.target;
diff --git a/src/runtime/dragon/dragongltexture_p.h b/src/runtime/dragon/dragongltexture_p.h
index 6d75bd5..a490db9 100644
--- a/src/runtime/dragon/dragongltexture_p.h
+++ b/src/runtime/dragon/dragongltexture_p.h
@@ -59,6 +59,7 @@ struct GLTexture
     QAbstractTexture::Target actualTarget = QAbstractTexture::TargetAutomatic;
     TextureProperties properties;
     TextureParameters parameters;
+    Immutable<LoadedTexture> loadedTexture;
 
     QSize size() const { return QSize(properties.width, properties.height); }
 
diff --git a/src/runtime/dragon/dragonrenderer.cpp b/src/runtime/dragon/dragonrenderer.cpp
index 09a1191..afe93db 100644
--- a/src/runtime/dragon/dragonrenderer.cpp
+++ b/src/runtime/dragon/dragonrenderer.cpp
@@ -399,12 +399,17 @@ Renderer::Frame Renderer::doRender(Renderer::Frame frame)
             // TODO not nice to have to take this by reference, but what can we do?
             auto createGLTextureHelper =
                     [&activeSurface](const QNodeId &id, const Immutable<LoadedTexture> &loadedTexture) {
-                        Q_UNUSED(id);
-                        return createGlTexture(loadedTexture, activeSurface.openGLContext());
-                    };
+                    Q_UNUSED(id);
+                    return Mutable<GLTexture>(createGlTexture(loadedTexture, activeSurface.openGLContext()));
+            };
+
+            auto compareGLTexture = [](const GLTexture &glTexture, const Immutable<LoadedTexture> &loaded){
+                return glTexture.loadedTexture == loaded;
+            };
 
             frame.uploadedTextures = synchronizeNew(std::move(frame.uploadedTextures),
                                                     loadedTextures,
+                                                    compareGLTexture,
                                                     createGLTextureHelper);
 
             auto updateGLTextureHelper = [&activeSurface](const QNodeId &id, Mutable<GLTexture> glTexture,
diff --git a/src/runtime/dragon/dragontexture.cpp b/src/runtime/dragon/dragontexture.cpp
index ea786de..7e181a5 100644
--- a/src/runtime/dragon/dragontexture.cpp
+++ b/src/runtime/dragon/dragontexture.cpp
@@ -30,12 +30,14 @@
 
 #include "dragontexture_p.h"
 
+#include <private/dragontextureimage_p.h>
+#include <private/dragoncomparegenerators_p.h>
+
 #include <Qt3DRender/private/qabstracttexture_p.h>
 #include <Qt3DCore/QPropertyUpdatedChange>
 #include <Qt3DCore/QPropertyNodeAddedChange>
 #include <Qt3DCore/QPropertyNodeRemovedChange>
 
-
 QT_BEGIN_NAMESPACE
 using namespace Qt3DCore;
 
@@ -189,6 +191,16 @@ void Texture::initializeFromPeer(const Qt3DCore::QNodeCreatedChangeBasePtr &chan
     addDirtyFlag(DirtyFlags(DirtyImageGenerators|DirtyProperties|DirtyParameters));
 }
 
+bool operator ==(const LoadedTexture &a, const LoadedTexture &b)
+{
+    return a.images == b.images && a.texture == b.texture;
+}
+
+bool operator ==(const Texture &a, const Texture &b)
+{
+    return compareGenerators(a.generator, b.generator) && a.properties == b.properties && a.parameters == b.parameters;
+}
+
 
 }
 }
diff --git a/src/runtime/dragon/dragontexture_p.h b/src/runtime/dragon/dragontexture_p.h
index b53e6e8..435416b 100644
--- a/src/runtime/dragon/dragontexture_p.h
+++ b/src/runtime/dragon/dragontexture_p.h
@@ -49,6 +49,8 @@
 
 #include <Qt3DRender/qtexturedata.h>
 
+#include <private/q3dsruntimeglobal_p.h>
+
 #include <private/dragonimmutable_p.h>
 
 #include <QFuture>
@@ -110,7 +112,7 @@ struct TextureParameters
     inline bool operator!=(const TextureParameters &o) const { return !(*this == o); }
 };
 
-class Texture : public BackendNode
+class Q3DSV_PRIVATE_EXPORT Texture : public BackendNode
 {
 public:
     enum DirtyFlag {
@@ -139,6 +141,8 @@ public:
     //    QVector<Qt3DCore::QNodeId> m_textureImages;
 };
 
+bool operator ==(const Texture &a, const Texture &b);
+
 // TODO add support for texture generators and not just texture images
 struct LoadedTexture
 {
@@ -149,6 +153,8 @@ struct LoadedTexture
     QTextureDataPtr data;
 };
 
+bool operator ==(const LoadedTexture &a, const LoadedTexture &b);;
+
 } // namespace Dragon
 } // namespace Qt3DRender
 QT_END_NAMESPACE
diff --git a/src/runtime/dragon/dragontextureimage.cpp b/src/runtime/dragon/dragontextureimage.cpp
index 58872fe..fca57de 100644
--- a/src/runtime/dragon/dragontextureimage.cpp
+++ b/src/runtime/dragon/dragontextureimage.cpp
@@ -30,6 +30,8 @@
 
 #include "dragontextureimage_p.h"
 
+#include <private/dragoncomparegenerators_p.h>
+
 #include <Qt3DRender/qabstracttextureimage.h>
 #include <Qt3DRender/private/qabstracttextureimage_p.h>
 
@@ -79,6 +81,16 @@ void TextureImage::sceneChangeEvent(const Qt3DCore::QSceneChangePtr &e)
     BackendNode::sceneChangeEvent(e);
 }
 
+bool operator ==(const TextureImage &a, const TextureImage &b)
+{
+    return compareGenerators(a.generator, b.generator) && a.face == b.face && a.layer == b.layer && a.mipLevel == b.mipLevel;
+}
+
+bool operator ==(const LoadedTextureImage &a, const LoadedTextureImage &b)
+{
+    return *a.generator == *b.generator;
+}
+
 }
 }
 QT_END_NAMESPACE
diff --git a/src/runtime/dragon/dragontextureimage_p.h b/src/runtime/dragon/dragontextureimage_p.h
index e9da84d..441f3be 100644
--- a/src/runtime/dragon/dragontextureimage_p.h
+++ b/src/runtime/dragon/dragontextureimage_p.h
@@ -92,6 +92,7 @@ struct LoadedTextureImage
     QTextureImageDataPtr data;
 };
 
+bool operator ==(const LoadedTextureImage &a, const LoadedTextureImage &b);
 
 } // namespace Dragon
 } // namespace Qt3DRender