Share and enable shader disk cache in QRhi OpenGL backend

The expectation for it is to function identically to what we get with
QOpenGLShaderProgram. (same environment variables, same logging
categories, etc.).

QOpenGLProgramBinaryCache is now shared between the QOpenGL convenience
classes (like QOpenGLShaderProgram) and QRhi. To achieve more modularity
and to prepare for QOpenGLShaderProgram and friends moving out of QtGui,
this class cannot depend on QOpenGLShader* anymore. This involves adding
some minor conversions between QRhi and QOpenGL enums for example.

Change-Id: I2f4664e074823ea536281aea8006a6db159a7381
Reviewed-by: Christian Strømme <christian.stromme@qt.io>

1 files changed, 39 insertions, 4 deletions

diff --git a/src/gui/opengl/qopenglprogrambinarycache_p.h b/src/gui/opengl/qopenglprogrambinarycache_p.h
index fb01e61872..f1cf24cd87 100644
--- a/src/gui/opengl/qopenglprogrambinarycache_p.h
+++ b/src/gui/opengl/qopenglprogrambinarycache_p.h
@@ -52,21 +52,26 @@
 //
 
 #include <QtGui/qtguiglobal.h>
-#include <QtGui/qopenglshaderprogram.h>
 #include <QtCore/qcache.h>
 #include <QtCore/qmutex.h>
+#include <QtGui/private/qopenglcontext_p.h>
+#include <QtGui/private/qshader_p.h>
 
 QT_BEGIN_NAMESPACE
 
+// These classes are also used by the OpenGL backend of QRhi. They must
+// therefore stay independent from QOpenGLShader(Program). Must rely only on
+// QOpenGLContext/Functions.
+
 class QOpenGLProgramBinaryCache
 {
 public:
     struct ShaderDesc {
         ShaderDesc() { }
-        ShaderDesc(QOpenGLShader::ShaderType type, const QByteArray &source = QByteArray())
-          : type(type), source(source)
+        ShaderDesc(QShader::Stage stage, const QByteArray &source = QByteArray())
+          : stage(stage), source(source)
         { }
-        QOpenGLShader::ShaderType type;
+        QShader::Stage stage;
         QByteArray source;
     };
     struct ProgramDesc {
@@ -104,6 +109,36 @@ private:
     QMutex m_mutex;
 };
 
+// While unlikely, one application can in theory use contexts with different versions
+// or profiles. Therefore any version- or extension-specific checks must be done on a
+// per-context basis, not just once per process. QOpenGLSharedResource enables this,
+// although it's once-per-sharing-context-group, not per-context. Still, this should
+// be good enough in practice.
+class QOpenGLProgramBinarySupportCheck : public QOpenGLSharedResource
+{
+public:
+    QOpenGLProgramBinarySupportCheck(QOpenGLContext *context);
+    void invalidateResource() override { }
+    void freeResource(QOpenGLContext *) override { }
+
+    bool isSupported() const { return m_supported; }
+
+private:
+    bool m_supported;
+};
+
+class QOpenGLProgramBinarySupportCheckWrapper
+{
+public:
+    QOpenGLProgramBinarySupportCheck *get(QOpenGLContext *context)
+    {
+        return m_resource.value<QOpenGLProgramBinarySupportCheck>(context);
+    }
+
+private:
+    QOpenGLMultiGroupSharedResource m_resource;
+};
+
 QT_END_NAMESPACE
 
 #endif