Refactor buffer handling

We cannot support bindToTexture() functions. On some
platforms the texture is provided by the driver. Therefore,
the HW integration must always provide a texture.

This has the added bonus of unifying the two separate code paths
that were introduced when EGLStream support was added.

Add a separate buffer manager that owns all buffers.
Don't destroy buffer objects on release. The client will probably
attach them again later. Also, release shm buffers immediately
after uploading to texture (needs to be documented that image()
will not work afterwards).

Make the old SurfaceBuffer class into an abstract base class,
so we can store state in the buffer class instead of having
to map from the wl_resource in each buffer integration. Move
the shared memory buffer handling into a separate subclass.

Change-Id: I81e471d13c92913d31ea1efe487f93fa908b5e0c
Reviewed-by: Dominik Holland <dominik.holland@pelagicore.com>
Reviewed-by: Louai Al-Khanji <louai.al-khanji@qt.io>
Reviewed-by: Johan Helsing <johan.helsing@qt.io>

1 files changed, 18 insertions, 40 deletions

diff --git a/src/compositor/compositor_api/qwaylandquickitem.cpp b/src/compositor/compositor_api/qwaylandquickitem.cpp
index a3234cba6..f41a4c3ee 100644
--- a/src/compositor/compositor_api/qwaylandquickitem.cpp
+++ b/src/compositor/compositor_api/qwaylandquickitem.cpp
@@ -50,6 +50,7 @@
 #include <QtGui/QGuiApplication>
 #include <QtGui/QScreen>
 #include <QtGui/QOpenGLFunctions>
+#include <QtGui/QOpenGLTexture>
 
 #include <QtQuick/QSGSimpleTextureNode>
 #include <QtQuick/QQuickWindow>
@@ -188,52 +189,40 @@ QWaylandBufferMaterial::QWaylandBufferMaterial(QWaylandBufferRef::BufferFormatEg
 
 QWaylandBufferMaterial::~QWaylandBufferMaterial()
 {
-    QOpenGLFunctions *gl = QOpenGLContext::currentContext()->functions();
-
-    for (GLuint texture : m_textures)
-        gl->glDeleteTextures(1, &texture);
 }
 
-void QWaylandBufferMaterial::setTextureForPlane(int plane, uint texture)
+void QWaylandBufferMaterial::setTextureForPlane(int plane, QOpenGLTexture *texture)
 {
     if (plane < 0 || plane >= bufferTypes[m_format].planeCount) {
         qWarning("plane index is out of range");
         return;
     }
 
-    QOpenGLFunctions *gl = QOpenGLContext::currentContext()->functions();
-    const GLenum target = bufferTypes[m_format].textureTarget;
-
-    gl->glBindTexture(target, texture);
-    setTextureParameters(target);
+    texture->bind();
+    setTextureParameters(texture->target());
 
     ensureTextures(plane - 1);
 
-    if (m_textures.size() <= plane) {
+    if (m_textures.size() <= plane)
         m_textures << texture;
-    } else {
-        std::swap(m_textures[plane], texture);
-        gl->glDeleteTextures(1, &texture);
-    }
+    else
+        m_textures[plane] = texture;
 }
 
 void QWaylandBufferMaterial::bind()
 {
-    QOpenGLFunctions *gl = QOpenGLContext::currentContext()->functions();
-    const GLenum target = bufferTypes[m_format].textureTarget;
-
     ensureTextures(bufferTypes[m_format].planeCount);
 
     switch (m_textures.size()) {
     case 3:
-        gl->glActiveTexture(GL_TEXTURE2);
-        gl->glBindTexture(target, m_textures[2]);
+        if (m_textures[2])
+            m_textures[2]->bind(GL_TEXTURE2);
     case 2:
-        gl->glActiveTexture(GL_TEXTURE1);
-        gl->glBindTexture(target, m_textures[1]);
+        if (m_textures[1])
+            m_textures[1]->bind(GL_TEXTURE1);
     case 1:
-        gl->glActiveTexture(GL_TEXTURE0);
-        gl->glBindTexture(target, m_textures[0]);
+        if (m_textures[0])
+            m_textures[0]->bind(GL_TEXTURE0);
     }
 }
 
@@ -260,15 +249,8 @@ void QWaylandBufferMaterial::setTextureParameters(GLenum target)
 //TODO move this into a separate centralized texture management class
 void QWaylandBufferMaterial::ensureTextures(int count)
 {
-    QOpenGLFunctions *gl = QOpenGLContext::currentContext()->functions();
-    const GLenum target = bufferTypes[m_format].textureTarget;
-    GLuint texture;
-
     for (int plane = m_textures.size(); plane < count; plane++) {
-        gl->glGenTextures(1, &texture);
-        gl->glBindTexture(target, texture);
-        setTextureParameters(target);
-        m_textures << texture;
+        m_textures << nullptr;
     }
 }
 
@@ -308,11 +290,8 @@ public:
                     opt |= QQuickWindow::TextureHasAlphaChannel;
                 }
 
-                GLuint texture;
-                glGenTextures(1, &texture);
-                glBindTexture(GL_TEXTURE_2D, texture);
-                buffer.bindToTexture();
-                m_sgTex = surfaceItem->window()->createTextureFromId(texture , QSize(surfaceItem->width(), surfaceItem->height()), opt);
+                auto texture = buffer.toOpenGLTexture();
+                m_sgTex = surfaceItem->window()->createTextureFromId(texture->textureId() , QSize(surfaceItem->width(), surfaceItem->height()), opt);
             }
         }
         emit textureChanged();
@@ -1151,6 +1130,7 @@ QSGNode *QWaylandQuickItem::updatePaintNode(QSGNode *oldNode, UpdatePaintNodeDat
                                 : QRectF(0, 0, width(), height());
 
     if (ref.isSharedMemory() || bufferTypes[ref.bufferFormatEgl()].canProvideTexture) {
+        // This case could covered by the more general path below, but this is more efficient (especially when using ShaderEffect items).
         QSGSimpleTextureNode *node = static_cast<QSGSimpleTextureNode *>(oldNode);
 
         if (!node) {
@@ -1193,13 +1173,11 @@ QSGNode *QWaylandQuickItem::updatePaintNode(QSGNode *oldNode, UpdatePaintNodeDat
         if (d->newTexture) {
             d->newTexture = false;
             for (int plane = 0; plane < bufferTypes[ref.bufferFormatEgl()].planeCount; plane++)
-                if (uint texture = ref.textureForPlane(plane))
+                if (auto texture = ref.toOpenGLTexture(plane))
                     material->setTextureForPlane(plane, texture);
             material->bind();
-            ref.bindToTexture();
         }
 
-        ref.updateTexture();
         QSGGeometry::updateTexturedRectGeometry(geometry, rect, QRectF(0, 0, 1, 1));
 
         node->setGeometry(geometry);