Fix for QTBUG-22693

This fix stops the stack from being unitentionally cleared. It also
ensures that a bound texture has a defined context.

Task-number: QTBUG-22693
Change-Id: I9f5f8d91849a8e63f04094f5fba6c47d9941a67d
Reviewed-by: Alex Wilson <alex.wilson@nokia.com>

6 files changed, 48 insertions, 52 deletions

diff --git a/src/imports/threed/viewport.cpp b/src/imports/threed/viewport.cpp
index cfa9c6bc1..9c062f1e7 100644
--- a/src/imports/threed/viewport.cpp
+++ b/src/imports/threed/viewport.cpp
@@ -885,8 +885,7 @@ void Viewport::render(QGLPainter *painter)
     // boundingRect is in local coordinates. We need to map it to the scene coordinates
     // in order to render to correct area.
     QRect viewport = mapRectToScene(boundingRect()).toRect();
-    qreal adjust = 1.0f;
-    ViewportSubsurface surface(painter->currentSurface(), viewport, adjust);
+    QGLSubsurface surface (painter->currentSurface(), viewport);
     painter->pushSurface(&surface);
 
     // Perform early drawing operations.
diff --git a/src/threed/textures/qgltexture2d.cpp b/src/threed/textures/qgltexture2d.cpp
index 81022296c..bdfc63171 100644
--- a/src/threed/textures/qgltexture2d.cpp
+++ b/src/threed/textures/qgltexture2d.cpp
@@ -41,7 +41,6 @@
 
 #include "qgltexture2d.h"
 #include "qgltexture2d_p.h"
-#include "qgltextureutils_p.h"
 #include "qglpainter_p.h"
 #include "qglext_p.h"
 
@@ -613,8 +612,8 @@ bool QGLTexture2DPrivate::bind(GLenum target)
 
     if (ctx)
     {
-        QGLPainter painter(ctx);
-        if (!painter.hasOpenGLFeature(QOpenGLFunctions::NPOTTextures))
+        QOpenGLFunctions functions(ctx);
+        if (!functions.hasOpenGLFeature(QOpenGLFunctions::NPOTTextures))
         {
             QSize oldSize = size;
             size = QGL::nextPowerOfTwo(size);
@@ -648,9 +647,10 @@ bool QGLTexture2DPrivate::bind(GLenum target)
             prev = info;
             info = info->next;
         }
-    } else {
+    }
+    if (!info) {
         info = new QGLTexture2DTextureInfo
-            (ctx, 0, imageGeneration - 1, parameterGeneration - 1);
+            (0, 0, imageGeneration - 1, parameterGeneration - 1);
         if (prev)
             prev->next = info;
         else
diff --git a/src/threed/textures/qgltexture2d_p.h b/src/threed/textures/qgltexture2d_p.h
index c7b7a4397..74bea3f56 100644
--- a/src/threed/textures/qgltexture2d_p.h
+++ b/src/threed/textures/qgltexture2d_p.h
@@ -56,6 +56,7 @@
 #include "qgltexture2d.h"
 #include "qgltextureutils_p.h"
 #include "qurl.h"
+#include <QDebug>
 
 #include <QAtomicInt>
 #include <QImage>
@@ -66,15 +67,15 @@ class QGLTexture2DTextureInfo
 {
 public:
     QGLTexture2DTextureInfo
-            (QOpenGLContext *context, GLuint textureId, uint imageGeneration,
-             uint parameterGeneration, bool isLiteral = false)
+            (QOpenGLContext *context, GLuint textureId, uint _imageGeneration,
+             uint _parameterGeneration, bool _isLiteral = false)
+        : imageGeneration(_imageGeneration)
+        , parameterGeneration(_parameterGeneration)
+        , isLiteral(_isLiteral)
+        , next(0)
     {
         if (textureId)
             tex.setTextureId(context, textureId);
-        this->imageGeneration = imageGeneration;
-        this->parameterGeneration = parameterGeneration;
-        this->isLiteral = isLiteral;
-        this->next = 0;
     }
 
     QGLBoundTexture tex;
diff --git a/src/threed/textures/qgltextureutils.cpp b/src/threed/textures/qgltextureutils.cpp
index ffc11c123..22eac8ca3 100644
--- a/src/threed/textures/qgltextureutils.cpp
+++ b/src/threed/textures/qgltextureutils.cpp
@@ -54,8 +54,7 @@ inline static bool isPowerOfTwo(int x)
 }
 
 QGLTextureExtensions::QGLTextureExtensions(QOpenGLContext *ctx)
-    : QOpenGLSharedResource(ctx->shareGroup())
-    , npotTextures(false)
+    : npotTextures(false)
     , generateMipmap(false)
     , bgraTextureFormat(false)
     , ddsTextureCompression(false)
@@ -95,6 +94,7 @@ QGLTextureExtensions::QGLTextureExtensions(QOpenGLContext *ctx)
 struct QGLTEHelper
 {
     QGLTextureExtensions *d;
+//    QGLTEHelper():d(0){qWarning("INITIALISE");}
 };
 
 Q_GLOBAL_STATIC(QGLTEHelper, qt_qgltehelper)
@@ -119,9 +119,10 @@ static void qt_gl_destroyTextureId(GLuint id)
 }
 
 QGLBoundTexture::QGLBoundTexture()
-    : m_resource(qt_gl_destroyTextureId)
-    , m_options(QGLTexture2D::DefaultBindOption)
+    : m_options(QGLTexture2D::DefaultBindOption)
     , m_hasAlpha(false)
+    , m_context(0)
+    , m_resourceId(0)
 {
 }
 
@@ -129,7 +130,7 @@ QGLBoundTexture::~QGLBoundTexture()
 {
 }
 
-// #define QGL_BIND_TEXTURE_DEBUG
+//#define QGL_BIND_TEXTURE_DEBUG
 
 void QGLBoundTexture::startUpload(QOpenGLContext *ctx, GLenum target, const QSize &imageSize)
 {
@@ -152,15 +153,14 @@ void QGLBoundTexture::startUpload(QOpenGLContext *ctx, GLenum target, const QSiz
 
     // Create the texture id for the target, which should be one of
     // GL_TEXTURE_2D or GL_TEXTURE_CUBE_MAP.
-    GLuint id = m_resource.id();
-    if (id) {
+    if (m_resourceId) {
         glBindTexture(target, 0);   // Just in case texture is bound.
-        m_resource.destroy();
+        glDeleteTextures(1, &m_resourceId);
     }
-    id = 0;
-    glGenTextures(1, &id);
-    glBindTexture(target, id);
-    m_resource.attach(ctx, id);
+    m_resourceId = 0;
+    glGenTextures(1, &m_resourceId);
+    glBindTexture(target, m_resourceId);
+    m_context = ctx;
 
     GLuint filtering = m_options & QGLTexture2D::LinearFilteringBindOption ? GL_LINEAR : GL_NEAREST;
 
@@ -588,17 +588,15 @@ bool QGLBoundTexture::bindCompressedTextureDDS(const char *buf, int len)
     const GLubyte *pixels =
         reinterpret_cast<const GLubyte *>(buf + ddsHeader->dwSize + 4);
 
-    GLuint id = m_resource.id();
-    if (id) {
+    if (m_resourceId) {
         glBindTexture(GL_TEXTURE_2D, 0);    // Just in case it is bound.
-        m_resource.destroy();
+        glDeleteTextures(1, &m_resourceId);
     }
-    id = 0;
-    glGenTextures(1, &id);
-    glBindTexture(GL_TEXTURE_2D, id);
     q_glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
     q_glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
-    m_resource.attach(QOpenGLContext::currentContext(), id);
+    m_resourceId = 0;
+    glGenTextures(1, &m_resourceId);
+    glBindTexture(GL_TEXTURE_2D, m_resourceId);
 
     int size;
     int offset = 0;
@@ -694,15 +692,13 @@ bool QGLBoundTexture::bindCompressedTexturePVR(const char *buf, int len)
 
     // Create the texture.
     glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
-    GLuint id = m_resource.id();
-    if (id) {
+    if (m_resourceId) {
         glBindTexture(GL_TEXTURE_2D, 0);    // Just in case it is bound.
-        m_resource.destroy();
+        glDeleteTextures(1, &m_resourceId);
     }
-    id = 0;
-    glGenTextures(1, &id);
-    glBindTexture(GL_TEXTURE_2D, id);
-    m_resource.attach(QOpenGLContext::currentContext(), id);
+    m_resourceId = 0;
+    glGenTextures(1, &m_resourceId);
+    glBindTexture(GL_TEXTURE_2D, m_resourceId);
     if (pvrHeader->mipMapCount) {
         if ((m_options & QGLTexture2D::LinearFilteringBindOption) != 0) {
             glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
diff --git a/src/threed/textures/qgltextureutils_p.h b/src/threed/textures/qgltextureutils_p.h
index 962ba52a2..fa819646b 100644
--- a/src/threed/textures/qgltextureutils_p.h
+++ b/src/threed/textures/qgltextureutils_p.h
@@ -59,7 +59,6 @@
 
 #include "qglnamespace.h"
 #include "qopenglfunctions.h"
-#include "qglsharedresource_p.h"
 #include "qgltexture2d.h"
 
 #include <private/qopenglcontext_p.h>
@@ -101,7 +100,7 @@ QT_BEGIN_NAMESPACE
 typedef void (QOPENGLF_APIENTRYP q_glCompressedTexImage2DARB)
     (GLenum, GLint, GLenum, GLsizei, GLsizei, GLint, GLsizei, const GLvoid *);
 
-class QGLTextureExtensions : public QOpenGLSharedResource
+class QGLTextureExtensions
 {
 public:
     QGLTextureExtensions(QOpenGLContext *ctx);
@@ -116,10 +115,6 @@ public:
     q_glCompressedTexImage2DARB compressedTexImage2D;
 
     static QGLTextureExtensions *extensions();
-
-    void invalidateResource() {}
-    void freeResource(QOpenGLContext *) {}
-
 };
 
 class QGLBoundTexture
@@ -128,12 +123,16 @@ public:
     QGLBoundTexture();
     ~QGLBoundTexture();
 
-    const QOpenGLContext *context() const { return m_resource.context(); }
+    QOpenGLContext *context() const {
+        return m_context;
+    }
 
-    GLuint textureId() const { return m_resource.id(); }
+    GLuint textureId() const { return m_resourceId; }
     void setTextureId(QOpenGLContext *ctx, GLuint id)
-        { m_resource.attach(ctx, id); }
-    void clearId() { m_resource.clearId(); }
+    {
+        m_context = ctx; m_resourceId = id;
+    }
+    void clearId() { m_resourceId = 0; m_context = 0; }
 
     QGLTexture2D::BindOptions options() const { return m_options; }
     void setOptions(QGLTexture2D::BindOptions options) { m_options = options; }
@@ -158,11 +157,12 @@ public:
     bool bindCompressedTexturePVR(const char *buf, int len);
 
 private:
-    QGLSharedResource m_resource;
     QGLTexture2D::BindOptions m_options;
     QSize m_size;
     bool m_hasAlpha;
     QTime time;
+    QOpenGLContext *m_context;
+    GLuint m_resourceId;
 };
 
 QT_END_NAMESPACE
diff --git a/src/threed/textures/textures.pri b/src/threed/textures/textures.pri
index d4c295794..3bab2a253 100644
--- a/src/threed/textures/textures.pri
+++ b/src/threed/textures/textures.pri
@@ -6,11 +6,11 @@ HEADERS += \
     textures/qareaallocator.h
 SOURCES += \
     qareaallocator.cpp \
-    qglsharedresource.cpp \
     qgltexture2d.cpp \
     qgltexturecube.cpp \
     qgltextureutils.cpp
 PRIVATE_HEADERS += \
-    qglsharedresource_p.h \
     qgltexture2d_p.h \
     qgltextureutils_p.h
+
+