rhi: Make it possible to request making the context current on GL

Needed by Qt Quick to handle cases where the application (or other Qt)
code contains OpenGL calls, and Qt Quick facilitates this by ensuring
the scenegraph's GL context is current. The expectation is that when
running with the GL backend of the rhi, all such code remains fully
functional. So add a makeCurrent type of call into the QRhi API that is
a no-op with anything other than OpenGL.

Change-Id: I6f774bf828e31802bdab0c3fef9421cdc0cebe5c
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
 
 
 
 
 
 

13 files changed, 49 insertions, 0 deletions

diff --git a/src/gui/rhi/qrhi.cpp b/src/gui/rhi/qrhi.cpp
index 8cd4813723..f599f16d21 100644
--- a/src/gui/rhi/qrhi.cpp
+++ b/src/gui/rhi/qrhi.cpp
@@ -4444,6 +4444,20 @@ const QRhiNativeHandles *QRhi::nativeHandles()
 }
 
 /*!
+    With OpenGL this makes the OpenGL context current on the current thread.
+    The function has no effect with other backends.
+
+    Calling this function is relevant typically in Qt framework code, when one
+    has to ensure external OpenGL code provided by the application can still
+    run like it did before with direct usage of OpenGL, as long as the QRhi is
+    using the OpenGL backend.
+ */
+void QRhi::makeThreadLocalNativeContextCurrent()
+{
+    d->makeThreadLocalNativeContextCurrent();
+}
+
+/*!
     \return the associated QRhiProfiler instance.
 
     An instance is always available for each QRhi, but it is not very useful
diff --git a/src/gui/rhi/qrhi_p.h b/src/gui/rhi/qrhi_p.h
index a0f57819e4..b7515cb17a 100644
--- a/src/gui/rhi/qrhi_p.h
+++ b/src/gui/rhi/qrhi_p.h
@@ -1352,6 +1352,7 @@ public:
     int resourceLimit(ResourceLimit limit) const;
 
     const QRhiNativeHandles *nativeHandles();
+    void makeThreadLocalNativeContextCurrent();
 
     QRhiProfiler *profiler();
 
diff --git a/src/gui/rhi/qrhi_p_p.h b/src/gui/rhi/qrhi_p_p.h
index 7c110431fb..de9bdae992 100644
--- a/src/gui/rhi/qrhi_p_p.h
+++ b/src/gui/rhi/qrhi_p_p.h
@@ -148,6 +148,7 @@ public:
     virtual int resourceLimit(QRhi::ResourceLimit limit) const = 0;
     virtual const QRhiNativeHandles *nativeHandles() = 0;
     virtual void sendVMemStatsToProfiler() = 0;
+    virtual void makeThreadLocalNativeContextCurrent() = 0;
 
     bool isCompressedFormat(QRhiTexture::Format format) const;
     void compressedFormatInfo(QRhiTexture::Format format, const QSize &size,
diff --git a/src/gui/rhi/qrhid3d11.cpp b/src/gui/rhi/qrhid3d11.cpp
index 07e67d95d9..6e5b0f751f 100644
--- a/src/gui/rhi/qrhid3d11.cpp
+++ b/src/gui/rhi/qrhid3d11.cpp
@@ -408,6 +408,11 @@ void QRhiD3D11::sendVMemStatsToProfiler()
     // nothing to do here
 }
 
+void QRhiD3D11::makeThreadLocalNativeContextCurrent()
+{
+    // nothing to do here
+}
+
 QRhiRenderBuffer *QRhiD3D11::createRenderBuffer(QRhiRenderBuffer::Type type, const QSize &pixelSize,
                                                 int sampleCount, QRhiRenderBuffer::Flags flags)
 {
diff --git a/src/gui/rhi/qrhid3d11_p_p.h b/src/gui/rhi/qrhid3d11_p_p.h
index fd5247b0b4..3942fa5076 100644
--- a/src/gui/rhi/qrhid3d11_p_p.h
+++ b/src/gui/rhi/qrhid3d11_p_p.h
@@ -563,6 +563,7 @@ public:
     int resourceLimit(QRhi::ResourceLimit limit) const override;
     const QRhiNativeHandles *nativeHandles() override;
     void sendVMemStatsToProfiler() override;
+    void makeThreadLocalNativeContextCurrent() override;
 
     void flushCommandBuffer();
     void enqueueSubresUpload(QD3D11Texture *texD, QD3D11CommandBuffer *cbD,
diff --git a/src/gui/rhi/qrhigles2.cpp b/src/gui/rhi/qrhigles2.cpp
index 0c89a9284f..a6a0bb257f 100644
--- a/src/gui/rhi/qrhigles2.cpp
+++ b/src/gui/rhi/qrhigles2.cpp
@@ -649,6 +649,14 @@ void QRhiGles2::sendVMemStatsToProfiler()
     // nothing to do here
 }
 
+void QRhiGles2::makeThreadLocalNativeContextCurrent()
+{
+    if (inFrame && !ofr.active)
+        ensureContext(currentSwapChain->surface);
+    else
+        ensureContext();
+}
+
 QRhiRenderBuffer *QRhiGles2::createRenderBuffer(QRhiRenderBuffer::Type type, const QSize &pixelSize,
                                                 int sampleCount, QRhiRenderBuffer::Flags flags)
 {
diff --git a/src/gui/rhi/qrhigles2_p_p.h b/src/gui/rhi/qrhigles2_p_p.h
index d1a8a1fadf..5254219bd6 100644
--- a/src/gui/rhi/qrhigles2_p_p.h
+++ b/src/gui/rhi/qrhigles2_p_p.h
@@ -574,6 +574,7 @@ public:
     int resourceLimit(QRhi::ResourceLimit limit) const override;
     const QRhiNativeHandles *nativeHandles() override;
     void sendVMemStatsToProfiler() override;
+    void makeThreadLocalNativeContextCurrent() override;
 
     bool ensureContext(QSurface *surface = nullptr) const;
     void executeDeferredReleases();
diff --git a/src/gui/rhi/qrhimetal.mm b/src/gui/rhi/qrhimetal.mm
index 8739a42738..6030f55d10 100644
--- a/src/gui/rhi/qrhimetal.mm
+++ b/src/gui/rhi/qrhimetal.mm
@@ -538,6 +538,11 @@ void QRhiMetal::sendVMemStatsToProfiler()
     // nothing to do here
 }
 
+void QRhiMetal::makeThreadLocalNativeContextCurrent()
+{
+    // nothing to do here
+}
+
 QRhiRenderBuffer *QRhiMetal::createRenderBuffer(QRhiRenderBuffer::Type type, const QSize &pixelSize,
                                                 int sampleCount, QRhiRenderBuffer::Flags flags)
 {
diff --git a/src/gui/rhi/qrhimetal_p_p.h b/src/gui/rhi/qrhimetal_p_p.h
index 039a5bdbf6..f9b9d96648 100644
--- a/src/gui/rhi/qrhimetal_p_p.h
+++ b/src/gui/rhi/qrhimetal_p_p.h
@@ -375,6 +375,7 @@ public:
     int resourceLimit(QRhi::ResourceLimit limit) const override;
     const QRhiNativeHandles *nativeHandles() override;
     void sendVMemStatsToProfiler() override;
+    void makeThreadLocalNativeContextCurrent() override;
 
     void executeDeferredReleases(bool forced = false);
     void finishActiveReadbacks(bool forced = false);
diff --git a/src/gui/rhi/qrhinull.cpp b/src/gui/rhi/qrhinull.cpp
index ad7b74a5c3..c764669058 100644
--- a/src/gui/rhi/qrhinull.cpp
+++ b/src/gui/rhi/qrhinull.cpp
@@ -166,6 +166,11 @@ void QRhiNull::sendVMemStatsToProfiler()
     // nothing to do here
 }
 
+void QRhiNull::makeThreadLocalNativeContextCurrent()
+{
+    // nothing to do here
+}
+
 QRhiRenderBuffer *QRhiNull::createRenderBuffer(QRhiRenderBuffer::Type type, const QSize &pixelSize,
                                                int sampleCount, QRhiRenderBuffer::Flags flags)
 {
diff --git a/src/gui/rhi/qrhinull_p_p.h b/src/gui/rhi/qrhinull_p_p.h
index da48b72656..6f79606486 100644
--- a/src/gui/rhi/qrhinull_p_p.h
+++ b/src/gui/rhi/qrhinull_p_p.h
@@ -268,6 +268,7 @@ public:
     int resourceLimit(QRhi::ResourceLimit limit) const override;
     const QRhiNativeHandles *nativeHandles() override;
     void sendVMemStatsToProfiler() override;
+    void makeThreadLocalNativeContextCurrent() override;
 
     QRhiNullNativeHandles nativeHandlesStruct;
     QRhiSwapChain *currentSwapChain = nullptr;
diff --git a/src/gui/rhi/qrhivulkan.cpp b/src/gui/rhi/qrhivulkan.cpp
index 1f80df6d0d..2d7b7a16f6 100644
--- a/src/gui/rhi/qrhivulkan.cpp
+++ b/src/gui/rhi/qrhivulkan.cpp
@@ -3457,6 +3457,11 @@ void QRhiVulkan::sendVMemStatsToProfiler()
                          stats.total.usedBytes, stats.total.unusedBytes));
 }
 
+void QRhiVulkan::makeThreadLocalNativeContextCurrent()
+{
+    // nothing to do here
+}
+
 QRhiRenderBuffer *QRhiVulkan::createRenderBuffer(QRhiRenderBuffer::Type type, const QSize &pixelSize,
                                                  int sampleCount, QRhiRenderBuffer::Flags flags)
 {
diff --git a/src/gui/rhi/qrhivulkan_p_p.h b/src/gui/rhi/qrhivulkan_p_p.h
index 01acc40d58..afb0cc1d5a 100644
--- a/src/gui/rhi/qrhivulkan_p_p.h
+++ b/src/gui/rhi/qrhivulkan_p_p.h
@@ -644,6 +644,7 @@ public:
     int resourceLimit(QRhi::ResourceLimit limit) const override;
     const QRhiNativeHandles *nativeHandles() override;
     void sendVMemStatsToProfiler() override;
+    void makeThreadLocalNativeContextCurrent() override;
 
     VkResult createDescriptorPool(VkDescriptorPool *pool);
     bool allocateDescriptorSet(VkDescriptorSetAllocateInfo *allocInfo, VkDescriptorSet *result, int *resultPoolIndex);