From 27ddd39a22058b28cf057ed5aae9433278670b81 Mon Sep 17 00:00:00 2001
From: Brad Davis <bdavis@saintandreas.org>
Date: Fri, 9 Sep 2016 09:30:38 -0700
Subject: [PATCH] PR comments

---
 libraries/gpu-gl/src/gpu/gl/GLShared.cpp      | 21 +++++++++++++++++++
 libraries/gpu-gl/src/gpu/gl/GLShared.h        |  6 ++++++
 .../gpu-gl/src/gpu/gl/GLTextureTransfer.cpp   |  4 ++--
 .../src/gpu/gl45/GL45BackendTexture.cpp       | 19 -----------------
 4 files changed, 29 insertions(+), 21 deletions(-)

diff --git a/libraries/gpu-gl/src/gpu/gl/GLShared.cpp b/libraries/gpu-gl/src/gpu/gl/GLShared.cpp
index fd6857c4c0..d59be0d9de 100644
--- a/libraries/gpu-gl/src/gpu/gl/GLShared.cpp
+++ b/libraries/gpu-gl/src/gpu/gl/GLShared.cpp
@@ -9,6 +9,8 @@
 
 #include <mutex>
 
+#include <QtCore/QThread>
+
 #include <GPUIdent.h>
 #include <NumericalConstants.h>
 #include <fstream>
@@ -933,9 +935,28 @@ void makeProgramBindings(ShaderObject& shaderObject) {
     (void)CHECK_GL_ERROR();
 }
 
+void serverWait() {
+    auto fence = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
+    assert(fence);
+    glWaitSync(fence, 0, GL_TIMEOUT_IGNORED);
+    glDeleteSync(fence);
+}
+
+void clientWait() {
+    auto fence = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
+    assert(fence);
+    auto result = glClientWaitSync(fence, GL_SYNC_FLUSH_COMMANDS_BIT, 0);
+    while (GL_TIMEOUT_EXPIRED == result || GL_WAIT_FAILED == result) {
+        // Minimum sleep
+        QThread::usleep(1);
+        result = glClientWaitSync(fence, 0, 0);
+    }
+    glDeleteSync(fence);
+}
 
 } }
 
+
 using namespace gpu;
 
 
diff --git a/libraries/gpu-gl/src/gpu/gl/GLShared.h b/libraries/gpu-gl/src/gpu/gl/GLShared.h
index 676d3910ff..7ec6deeb9d 100644
--- a/libraries/gpu-gl/src/gpu/gl/GLShared.h
+++ b/libraries/gpu-gl/src/gpu/gl/GLShared.h
@@ -18,6 +18,12 @@ Q_DECLARE_LOGGING_CATEGORY(gpugllogging)
 
 namespace gpu { namespace gl { 
 
+// Create a fence and inject a GPU wait on the fence
+void serverWait();
+
+// Create a fence and synchronously wait on the fence
+void clientWait();
+
 gpu::Size getDedicatedMemory();
 ComparisonFunction comparisonFuncFromGL(GLenum func);
 State::StencilOp stencilOpFromGL(GLenum stencilOp);
diff --git a/libraries/gpu-gl/src/gpu/gl/GLTextureTransfer.cpp b/libraries/gpu-gl/src/gpu/gl/GLTextureTransfer.cpp
index 0f64ea1182..ae8739bb3b 100644
--- a/libraries/gpu-gl/src/gpu/gl/GLTextureTransfer.cpp
+++ b/libraries/gpu-gl/src/gpu/gl/GLTextureTransfer.cpp
@@ -146,7 +146,7 @@ bool GLTextureTransferHelper::process() {
         gltexture->finishTransfer();
         glNamedFramebufferTexture(_readFramebuffer, GL_COLOR_ATTACHMENT0, gltexture->_id, 0);
         glBlitNamedFramebuffer(_readFramebuffer, _drawFramebuffer, 0, 0, 1, 1, 0, 0, 1, 1, GL_COLOR_BUFFER_BIT, GL_NEAREST);
-        glFinish();
+        clientWait();
         gltexture->_contentStamp = gltexture->_gpuObject.getDataStamp();
         gltexture->updateSize();
         gltexture->setSyncState(gpu::gl::GLSyncState::Transferred);
@@ -161,7 +161,7 @@ bool GLTextureTransferHelper::process() {
 
     if (!_transferringTextures.empty()) {
         // Don't saturate the GPU
-        glFinish();
+        clientWait();
     } else {
         // Don't saturate the CPU
         QThread::msleep(1);
diff --git a/libraries/gpu-gl/src/gpu/gl45/GL45BackendTexture.cpp b/libraries/gpu-gl/src/gpu/gl45/GL45BackendTexture.cpp
index db8186221c..871a2c8a03 100644
--- a/libraries/gpu-gl/src/gpu/gl45/GL45BackendTexture.cpp
+++ b/libraries/gpu-gl/src/gpu/gl45/GL45BackendTexture.cpp
@@ -32,25 +32,6 @@ GLTexture* GL45Backend::syncGPUObject(const TexturePointer& texture, bool transf
     return GL45Texture::sync<GL45Texture>(*this, texture, transfer);
 }
 
-void serverWait() {
-    auto fence = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
-    assert(fence);
-    glWaitSync(fence, 0, GL_TIMEOUT_IGNORED);
-    glDeleteSync(fence);
-}
-
-void clientWait() {
-    auto fence = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
-    assert(fence);
-    auto result = glClientWaitSync(fence, GL_SYNC_FLUSH_COMMANDS_BIT, 0);
-    while (GL_TIMEOUT_EXPIRED == result || GL_WAIT_FAILED == result) {
-        // Minimum sleep
-        QThread::usleep(1);
-        result = glClientWaitSync(fence, 0, 0);
-    }
-    glDeleteSync(fence);
-}
-
 TransferState::TransferState(GLTexture& texture) : _texture(texture) {
 }