Upload sizes to OpenGL only once per draw

Should fix MacOS issue

imagescrollareagl.cpp

@@ -67,6 +67,7 @@ ImageWidget::ImageWidget(Database *database, QWidget *parent) : QOpenGLWidget(pa
     m_updateTimer = new QTimer(this);
     m_updateTimer->setInterval(500);
     m_updateTimer->setSingleShot(true);
+    m_sizesDirty = false;
     connect(m_updateTimer, SIGNAL(timeout()), this, SLOT(update()));
     setAcceptDrops(true);
     QTimer::singleShot(1000, [this](){
@@ -147,11 +148,6 @@ void ImageWidget::allocateThumbnails(const QStringList &paths)
     m_thumbnailTexture->setSize(THUMB_SIZE, THUMB_SIZE);
     m_thumbnailTexture->setLayers(paths.size());
     m_thumbnailTexture->allocateStorage();
-    m_bufferSizes->bind();
-    float *tmp = new float[count*3];
-    memset(tmp, 0, count * sizeof(float)*3);
-    m_bufferSizes->allocate(tmp, count * sizeof(float)*3);
-    delete [] tmp;
 }
 
 void ImageWidget::setMTFParams(float low, float mid, float high)
@@ -209,8 +205,7 @@ void ImageWidget::thumbnailLoaded(const Image *image)
     m_thumbnailTexture->setData(0, image->number(), QOpenGLTexture::RGB, QOpenGLTexture::UInt16, raw->data(), m_transferOptions.get());
     float a = raw->thumbAspect();
     int sizes[3] = { std::max(1, a > 1.0f ? THUMB_SIZE : (int)(THUMB_SIZE * a)), std::max(1, a < 1.0f ? THUMB_SIZE : (int)(THUMB_SIZE / a)), image->number() };
-    m_bufferSizes->bind();
+    m_sizesDirty = true;
-    m_bufferSizes->write(image->number() * sizeof(sizes), sizes, sizeof(sizes));
     m_thumnails[image->number()].size = QSize(sizes[0], sizes[1]);
     if(!m_updateTimer->isActive())m_updateTimer->start();
 }
@@ -237,12 +232,26 @@ void ImageWidget::paintGL()
     {
         m_vaoThumb->bind();
         m_thumbnailTexture->bind(1);
+        if(m_sizesDirty)
+        {
+            m_bufferSizes->bind();
+            int i = 0;
+            std::vector<int> sizes(m_thumbnailCount*3);
+            for(auto &s : m_thumnails)
+            {
+                sizes[3*i]   = s.size.width();
+                sizes[3*i+1] = s.size.height();
+                sizes[3*i+2] = i;
+                i++;
+            }
+            m_bufferSizes->allocate(&sizes[0], sizes.size()*sizeof(int));
+            m_sizesDirty = false;
+        }
         m_thumbnailProgram->bind();
         f->glUniform3i(m_thumbnailProgram->uniformLocation("viewport_row"), width(), height(), width()/THUMB_SIZE_BORDER);
         m_thumbnailProgram->setUniformValue("mtf_param", m_low, m_mid, m_high);
         m_thumbnailProgram->setUniformValue("invert", m_invert);
         m_thumbnailProgram->setUniformValue("offset", 0, m_dy);
-        f3->glVertexAttribDivisor(m_thumbnailProgram->attributeLocation("imageSize_num"), 1);
         QMatrix4x4 mvp;
         mvp.ortho(rect());
         m_thumbnailProgram->setUniformValue("mvp", mvp);
@@ -378,8 +387,8 @@ void ImageWidget::initializeGL()
     m_bufferSizes->setUsagePattern(QOpenGLBuffer::StaticDraw);
     m_bufferSizes->create();
     m_bufferSizes->bind();
-
     m_bufferSizes->allocate(12);
+
     m_thumbnailProgram->enableAttributeArray("imageSize_num");
     m_thumbnailProgram->setAttributeBuffer("imageSize_num", GL_FLOAT, 0, 3);
     f3->glVertexAttribDivisor(m_thumbnailProgram->attributeLocation("imageSize_num"), 1);

imagescrollareagl.h

@@ -56,6 +56,7 @@ class ImageWidget : public QOpenGLWidget
     bool m_superpixel;
     bool m_showThumbnails;
     bool m_selecting;
+    bool m_sizesDirty;
     int m_thumbnailCount;
     QVector<ImageThumb> m_thumnails;
     Database *m_database;