Track which vertex attrib arrays are enabled in QGLContextPrivate

The GL2 engine (and probably Qt/3D) needs to track which vertex
attribute arrays are currently enabled and which are disabled. As
this is per-context state, the logical place to track this is in the
context and not in the paint engine.

This patch also makes the GL2 engine's shader manager enable/disable
the appropriate attribute arrays for a given shader program when it
is used.

Reviewed-By: Kim

1 files changed, 9 insertions, 0 deletions

diff --git a/src/opengl/qgl_p.h b/src/opengl/qgl_p.h
index 99c0f33..834ff96 100644
--- a/src/opengl/qgl_p.h
+++ b/src/opengl/qgl_p.h
@@ -257,6 +257,10 @@ private:
 
 class QGLTexture;
 
+// This probably needs to grow to GL_MAX_VERTEX_ATTRIBS, but 3 is ok for now as that's
+// all the GL2 engine uses:
+#define QT_GL_VERTEX_ARRAY_TRACKED_COUNT 3
+
 class QGLContextPrivate
 {
     Q_DECLARE_PUBLIC(QGLContext)
@@ -276,6 +280,9 @@ public:
 
     void cleanup();
 
+    void setVertexAttribArrayEnabled(int arrayIndex, bool enabled = true);
+    void syncGlState(); // Makes sure the GL context's state is what we think it is
+
 #if defined(Q_WS_WIN)
     HGLRC rc;
     HDC dc;
@@ -332,6 +339,8 @@ public:
     GLuint default_fbo;
     QPaintEngine *active_engine;
 
+    bool vertexAttributeArraysEnabledState[QT_GL_VERTEX_ARRAY_TRACKED_COUNT];
+
     static inline QGLContextGroup *contextGroup(const QGLContext *ctx) { return ctx->d_ptr->group; }
 
 #ifdef Q_WS_WIN