Working on build

libraries/gpu/src/gpu/Resource.cpp

@@ -282,11 +282,6 @@ void Buffer::markDirty(Size offset, Size bytes) {
     _pages.markRegion(offset, bytes);
 }
 
-void Buffer::applyUpdate(const Update& update) {
-    _renderPages = update.pages;
-     update.updateOperator(_renderSysmem);
- }
-
 Buffer::Update Buffer::getUpdate() const {
     static Update EMPTY_UPDATE;
     if (!_pages) {
@@ -319,6 +314,21 @@ Buffer::Update Buffer::getUpdate() const {
     return result;
 }
 
+void Buffer::applyUpdate(const Update& update) {
+    _renderPages = update.pages;
+    update.updateOperator(_renderSysmem);
+}
+
+void Buffer::flush() {
+    _renderPages = _pages;
+    _renderSysmem.resize(_sysmem.getSize());
+    auto dirtyPages = _pages.getMarkedPages();
+    for (Size page : dirtyPages) {
+        Size offset = page * _pages._pageSize;
+        memcpy(_renderSysmem.editData() + offset, _sysmem.readData() + offset, _pages._pageSize);
+    }
+}
+
 Buffer::Size Buffer::setData(Size size, const Byte* data) {
     resize(size);
     setSubData(0, size, data);

libraries/gpu/src/gpu/Resource.h

@@ -105,8 +105,6 @@ public:
     };
 
 protected:
-    using Sysmem = gpu::Sysmem;
-
     Resource() {}
     virtual ~Resource() {}
 
@@ -135,7 +133,7 @@ struct PageManager {
     uint8 _flags{ 0 };
     const Size _pageSize;
 
-    operator bool const() {
+    operator bool() const {
         return (*this)(DIRTY);
     }
 
@@ -346,6 +344,11 @@ public:
     // Main thread operation to say that the buffer is ready to be used as a frame
     Update getUpdate() const;
 
+    // For use by the render thread to avoid the intermediate step of getUpdate/applyUpdate
+    void flush();
+
+    // FIXME don't maintain a second buffer continuously.  We should be able to apply updates 
+    // directly to the GL object and discard _renderSysmem and _renderPages
     mutable PageManager _renderPages;
     Sysmem _renderSysmem;