Fix stereoscopic rendering with subpresentations

Viewports of subpresentations should not be reduced in
stereoscopic modes.

Task-number: QT3DS-4141
Change-Id: Ie96ff296bec2d11b215f36e08df23911f18fbba2
Reviewed-by: Antti Määttä <antti.maatta@qt.io>
Reviewed-by: Tomi Korpipää <tomi.korpipaa@qt.io>

6 files changed, 18 insertions, 6 deletions

diff --git a/src/runtimerender/Qt3DSRenderSubpresentation.cpp b/src/runtimerender/Qt3DSRenderSubpresentation.cpp
index 8b13361..834d773 100644
--- a/src/runtimerender/Qt3DSRenderSubpresentation.cpp
+++ b/src/runtimerender/Qt3DSRenderSubpresentation.cpp
@@ -81,6 +81,7 @@ namespace render {
                                           const SRenderInstanceId instanceId)
     {
         NVRenderRect theViewportSize(inRenderContext.GetViewport());
+        m_Presentation.m_Scene->m_IsSubPresentationScene = true;
         m_Presentation.m_Scene->Render(
             QT3DSVec2((QT3DSF32)theViewportSize.m_Width, (QT3DSF32)theViewportSize.m_Height),
             m_RenderContext, inClearColorBuffer, instanceId);
@@ -96,6 +97,7 @@ namespace render {
         Q_UNUSED(inEnvironment);
         Q_UNUSED(inPresScale);
         NVRenderRect theViewportSize(inRenderContext.GetViewport());
+        m_Presentation.m_Scene->m_IsSubPresentationScene = true;
         m_Presentation.m_Scene->RenderWithClear(
             QT3DSVec2((QT3DSF32)theViewportSize.m_Width, (QT3DSF32)theViewportSize.m_Height),
             m_RenderContext, inClearBuffer, inClearColor, id);
diff --git a/src/runtimerender/graphobjects/Qt3DSRenderScene.cpp b/src/runtimerender/graphobjects/Qt3DSRenderScene.cpp
index afe68d5..3d14f9c 100644
--- a/src/runtimerender/graphobjects/Qt3DSRenderScene.cpp
+++ b/src/runtimerender/graphobjects/Qt3DSRenderScene.cpp
@@ -42,6 +42,7 @@ SScene::SScene()
     , m_ClearColor(0.0f)
     , m_UseClearColor(true)
     , m_Dirty(true)
+    , m_IsSubPresentationScene(false)
 {
 }
 
diff --git a/src/runtimerender/graphobjects/Qt3DSRenderScene.h b/src/runtimerender/graphobjects/Qt3DSRenderScene.h
index 00a4591..a2f86b9 100644
--- a/src/runtimerender/graphobjects/Qt3DSRenderScene.h
+++ b/src/runtimerender/graphobjects/Qt3DSRenderScene.h
@@ -47,6 +47,7 @@ namespace render {
         QT3DSVec4 m_ClearColor;
         bool m_UseClearColor;
         bool m_Dirty;
+        bool m_IsSubPresentationScene;
 
         enum RenderClearCommand {
             ClearIsOptional = 0,
diff --git a/src/runtimerender/rendererimpl/Qt3DSRendererImplLayerRenderData.cpp b/src/runtimerender/rendererimpl/Qt3DSRendererImplLayerRenderData.cpp
index 3c6e1c3..9f06764 100644
--- a/src/runtimerender/rendererimpl/Qt3DSRendererImplLayerRenderData.cpp
+++ b/src/runtimerender/rendererimpl/Qt3DSRendererImplLayerRenderData.cpp
@@ -2090,10 +2090,12 @@ void SLayerRenderData::RunRenderPass(TRenderRenderableFunction inRenderFn,
             // transform.
             QT3DSMat44 theFinalMVP(QT3DSMat44::createIdentity());
             SCamera theTempCamera;
+            // When layer & scene are part of subpresentation, ignore stereoscopic viewport adjustments
+            bool noStereo = m_Layer.m_Scene && m_Layer.m_Scene->m_IsSubPresentationScene;
             NVRenderRect theLayerViewport(
-                thePrepResult.GetLayerToPresentationViewport().ToIntegerRect());
+                thePrepResult.GetLayerToPresentationViewport(noStereo).ToIntegerRect());
             NVRenderRect theLayerClip(
-                thePrepResult.GetLayerToPresentationScissorRect().ToIntegerRect());
+                thePrepResult.GetLayerToPresentationScissorRect(noStereo).ToIntegerRect());
 
             {
                 QT3DSMat33 ignored;
diff --git a/src/runtimerender/rendererimpl/Qt3DSRendererImplLayerRenderHelper.cpp b/src/runtimerender/rendererimpl/Qt3DSRendererImplLayerRenderHelper.cpp
index c28585e..a9c7f4c 100644
--- a/src/runtimerender/rendererimpl/Qt3DSRendererImplLayerRenderHelper.cpp
+++ b/src/runtimerender/rendererimpl/Qt3DSRendererImplLayerRenderHelper.cpp
@@ -207,8 +207,11 @@ NVRenderRectF SLayerRenderHelper::GetLayerRenderViewport() const
         return m_Viewport;
 }
 
-NVRenderRectF SLayerRenderHelper::GetLayerToPresentationViewport() const
+NVRenderRectF SLayerRenderHelper::GetLayerToPresentationViewport(bool noStereo) const
 {
+    if (noStereo)
+        return m_Viewport;
+
     if (m_StereoMode == StereoModes::LeftRight) {
         if (m_StereoView == StereoViews::Left) {
             return NVRenderRectF(m_Viewport.m_X, m_Viewport.m_Y, m_Viewport.m_Width/2,
@@ -231,8 +234,11 @@ NVRenderRectF SLayerRenderHelper::GetLayerToPresentationViewport() const
     return m_Viewport;
 }
 
-NVRenderRectF SLayerRenderHelper::GetLayerToPresentationScissorRect() const
+NVRenderRectF SLayerRenderHelper::GetLayerToPresentationScissorRect(bool noStereo) const
 {
+    if (noStereo)
+        return m_Scissor;
+
     if (m_StereoMode == StereoModes::LeftRight) {
         if (m_StereoView == StereoViews::Left) {
             return NVRenderRectF(m_Scissor.m_X, m_Scissor.m_Y,
diff --git a/src/runtimerender/rendererimpl/Qt3DSRendererImplLayerRenderHelper.h b/src/runtimerender/rendererimpl/Qt3DSRendererImplLayerRenderHelper.h
index 59f4e08..7d2254a 100644
--- a/src/runtimerender/rendererimpl/Qt3DSRendererImplLayerRenderHelper.h
+++ b/src/runtimerender/rendererimpl/Qt3DSRendererImplLayerRenderHelper.h
@@ -108,10 +108,10 @@ namespace render {
         // Does not differ whether offscreen or not, simply states how this layer maps to the
         // presentation
         NVRenderRectF getOriginalLayerToPresentationViewport() const;
-        NVRenderRectF GetLayerToPresentationViewport() const;
+        NVRenderRectF GetLayerToPresentationViewport(bool noStereo = false) const;
         // Does not differ whether offscreen or not, scissor rect of how this layer maps to
         // presentation.
-        NVRenderRectF GetLayerToPresentationScissorRect() const;
+        NVRenderRectF GetLayerToPresentationScissorRect(bool noStereo = false) const;
 
         QSize GetTextureDimensions() const;