Fixed eglStream compositing

When creating the eglStream from the fd we also need to create
the texture and call stream_consumer_gltexture. Otherwise
the wayland client can't create the wayland client surface.

Fixed the qwindow-compositor example to use the texture associated
to the QWaylandBufferRef when compositing a EXTERNAL_OES target.

QML compositing only works when QSG_RENDER_LOOP is set to basic
as we need to generate a texture from the gui thread.

As the texture is created by the bufferintegration it might end up
in a different gl context than the quick item using it. The texture
is also deleted together with the buffer, which prevents the use
of the texture afterwards. Both problems need to be fixed in follow
up commits.

Task-number: QTBUG-50850
Change-Id: Ifec67bbe9e4b2a680c871dc4aced37b71b7b6f80
Reviewed-by: Louai Al-Khanji <louai.al-khanji@qt.io>
Reviewed-by: Giulio Camuffo <giulio.camuffo@kdab.com>

3 files changed, 36 insertions, 10 deletions

diff --git a/examples/wayland/qwindow-compositor/compositorwindow.cpp b/examples/wayland/qwindow-compositor/compositorwindow.cpp
index 7e10a1739..537a3d08a 100644
--- a/examples/wayland/qwindow-compositor/compositorwindow.cpp
+++ b/examples/wayland/qwindow-compositor/compositorwindow.cpp
@@ -116,10 +116,18 @@ void CompositorWindow::paintGL()
     functions->glEnable(GL_BLEND);
     functions->glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
+    GLenum currentTarget = GL_TEXTURE_2D;
     Q_FOREACH (WindowCompositorView *view, m_compositor->views()) {
         if (view->isCursor())
             continue;
-        GLuint textureId = view->getTexture();
+        GLenum target;
+        GLuint textureId = view->getTexture(&target);
+        if (!textureId || !target)
+            continue;
+        if (target != currentTarget) {
+            currentTarget = target;
+            m_textureBlitter.bind(currentTarget);
+        }
         QWaylandSurface *surface = view->surface();
         if (surface && surface->isMapped()) {
             QSize s = surface->size();
diff --git a/examples/wayland/qwindow-compositor/windowcompositor.cpp b/examples/wayland/qwindow-compositor/windowcompositor.cpp
index bd39908e5..ecbbc5041 100644
--- a/examples/wayland/qwindow-compositor/windowcompositor.cpp
+++ b/examples/wayland/qwindow-compositor/windowcompositor.cpp
@@ -50,25 +50,42 @@
 #include <QtWaylandCompositor/qwaylanddrag.h>
 
 #include <QDebug>
+#include <QOpenGLContext>
+
+#ifndef GL_TEXTURE_EXTERNAL_OES
+#define GL_TEXTURE_EXTERNAL_OES 0x8D65
+#endif
 
 WindowCompositorView::WindowCompositorView()
-    : m_texture(0)
+    : m_textureTarget(GL_TEXTURE_2D)
+    , m_texture(0)
     , m_wlShellSurface(nullptr)
     , m_xdgSurface(nullptr)
     , m_xdgPopup(nullptr)
     , m_parentView(nullptr)
 {}
 
-GLuint WindowCompositorView::getTexture() {
+GLuint WindowCompositorView::getTexture(GLenum *target)
+{
+    QWaylandBufferRef buf = currentBuffer();
+    m_texture = buf.textureForPlane(0);
+
+    if (buf.bufferFormatEgl() == QWaylandBufferRef::BufferFormatEgl_EXTERNAL_OES)
+        m_textureTarget = GL_TEXTURE_EXTERNAL_OES;
+
     if (advance()) {
-        if (m_texture)
-            glDeleteTextures(1, &m_texture);
+        if (!m_texture)
+            glGenTextures(1, &m_texture);
 
-        glGenTextures(1, &m_texture);
-        glBindTexture(GL_TEXTURE_2D, m_texture);
-        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
-        currentBuffer().bindToTexture();
+        glBindTexture(m_textureTarget, m_texture);
+        buf.bindToTexture();
     }
+
+    buf.updateTexture();
+
+    if (target)
+        *target = m_textureTarget;
+
     return m_texture;
 }
 
diff --git a/examples/wayland/qwindow-compositor/windowcompositor.h b/examples/wayland/qwindow-compositor/windowcompositor.h
index 5290d7c85..80a7bebe4 100644
--- a/examples/wayland/qwindow-compositor/windowcompositor.h
+++ b/examples/wayland/qwindow-compositor/windowcompositor.h
@@ -59,7 +59,7 @@ class WindowCompositorView : public QWaylandView
     Q_OBJECT
 public:
     WindowCompositorView();
-    GLuint getTexture();
+    GLuint getTexture(GLenum *target = 0);
     QPointF position() const { return m_position; }
     void setPosition(const QPointF &pos) { m_position = pos; }
     bool isCursor() const;
@@ -72,6 +72,7 @@ public:
 
 private:
     friend class WindowCompositor;
+    GLenum m_textureTarget;
     GLuint m_texture;
     QPointF m_position;
     QWaylandWlShellSurface *m_wlShellSurface;