OpenGL: Fix content not updated when using OnDemand and switching textures

When changing a Parameter whose value is a texture, it takes Qt3D potentially
two frames to process the scene fully before it is able to draw the updated
content.

This patch makes it so that if we know we have the flags ParametersDirty for
frame N, we request to reprocess the scene once more on frame N+1.

Change-Id: Ia635e324434f92f8423a68b72d99350d96830de6
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
(cherry picked from commit 672da697b147f039effbfd352b20f3f1891f31c6)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/src/plugins/renderers/opengl/renderer/renderer.cpp b/src/plugins/renderers/opengl/renderer/renderer.cpp
index f6c44287e..37a9eafd9 100644
--- a/src/plugins/renderers/opengl/renderer/renderer.cpp
+++ b/src/plugins/renderers/opengl/renderer/renderer.cpp
@@ -1794,6 +1794,7 @@ std::vector<Qt3DCore::QAspectJobPtr> Renderer::renderBinJobs()
     // Remove previous dependencies
     m_cleanupJob->removeDependency(QWeakPointer<QAspectJob>());
 
+    const bool dirtyParametersForCurrentFrame = m_dirtyBits.marked & AbstractRenderer::ParameterDirty;
     const BackendNodeDirtySet dirtyBitsForFrame = m_dirtyBits.marked | m_dirtyBits.remaining;
     m_dirtyBits.marked = {};
     m_dirtyBits.remaining = {};
@@ -1910,6 +1911,10 @@ std::vector<Qt3DCore::QAspectJobPtr> Renderer::renderBinJobs()
 
     m_dirtyBits.remaining = dirtyBitsForFrame & notCleared;
 
+    // Dirty Parameters might need 2 frames to react if the parameter references a texture
+    if (dirtyParametersForCurrentFrame)
+        m_dirtyBits.remaining |= AbstractRenderer::ParameterDirty;
+
     return renderBinJobs;
 }