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VReaperVVReaperV
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Implement staging buffer and use it for material system
Adds `GLStagingBuffer` and `GLBufferCopy()`. `GLStagingBuffer` allows setting buffer storage and map flags to 0 on the destination buffers, which pretty much guarantees that they will go into VRAM. The data is uploaded through mapping `stagingBuffer` and doing a copy of the data on the GPU.
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8 files changed

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lines changed

8 files changed

+290
-58
lines changed

‎src.cmake

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@@ -97,6 +97,8 @@ set(RENDERERLIST
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${ENGINE_DIR}/renderer/GeometryCache.h
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${ENGINE_DIR}/renderer/GeometryOptimiser.cpp
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${ENGINE_DIR}/renderer/GeometryOptimiser.h
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${ENGINE_DIR}/renderer/GLMemory.cpp
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${ENGINE_DIR}/renderer/GLMemory.h
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${ENGINE_DIR}/renderer/InternalImage.cpp
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${ENGINE_DIR}/renderer/InternalImage.h
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${ENGINE_DIR}/renderer/Material.cpp

‎src/engine/renderer/BufferBind.h

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@@ -58,6 +58,7 @@ namespace BufferBind {
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COMMAND_COUNTERS_STORAGE = 9,
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TEX_DATA_STORAGE = 11,
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STAGING = 12,
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DEBUG = 10,
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‎src/engine/renderer/GLMemory.cpp

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/*
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===========================================================================
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Daemon BSD Source Code
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Copyright (c) 2025 Daemon Developers
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All rights reserved.
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This file is part of the Daemon BSD Source Code (Daemon Source Code).
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are met:
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* Redistributions of source code must retain the above copyright
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notice, this list of conditions and the following disclaimer.
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* Redistributions in binary form must reproduce the above copyright
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notice, this list of conditions and the following disclaimer in the
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documentation and/or other materials provided with the distribution.
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* Neither the name of the Daemon developers nor the
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names of its contributors may be used to endorse or promote products
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derived from this software without specific prior written permission.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
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ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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DISCLAIMED. IN NO EVENT SHALL DAEMON DEVELOPERS BE LIABLE FOR ANY
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DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
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ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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===========================================================================
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*/
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// GLMemory.cpp
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#include "common/Common.h"
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#include "GLMemory.h"
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// 128 MB, should be enough to fit anything in BAR without going overboard
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const GLsizeiptr GLStagingBuffer::SIZE = 128 * 1024 * 1024 / sizeof( uint32_t );
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GLStagingBuffer stagingBuffer;
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void GLBufferCopy( GLBuffer* src, GLBuffer* dst, GLintptr srcOffset, GLintptr dstOffset, GLsizeiptr size ) {
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glCopyNamedBufferSubData( src->id, dst->id,
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srcOffset * sizeof( uint32_t ), dstOffset * sizeof( uint32_t ), size * sizeof( uint32_t ) );
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}
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uint32_t* GLStagingBuffer::MapBuffer( const GLsizeiptr size ) {
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if ( size > SIZE ) {
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Sys::Drop( "Couldn't map GL staging buffer: size too large (%u/%u)", size, SIZE );
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}
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if ( pointer + size > SIZE ) {
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FlushAll();
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GLsync sync = glFenceSync( GL_SYNC_GPU_COMMANDS_COMPLETE, 0 );
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constexpr GLuint64 SYNC_TIMEOUT = 10000000000; // 10 seconds
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if ( glClientWaitSync( sync, GL_SYNC_FLUSH_COMMANDS_BIT, SYNC_TIMEOUT ) == GL_TIMEOUT_EXPIRED ) {
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Sys::Drop( "Failed GL staging buffer copy sync" );
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}
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glDeleteSync( sync );
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pointer = 0;
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current = 0;
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last = 0;
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}
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uint32_t* ret = buffer.GetData() + pointer;
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last = pointer;
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pointer += size;
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return ret;
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}
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void GLStagingBuffer::FlushBuffer() {
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buffer.FlushRange( current, pointer - current );
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GL_CheckErrors();
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current = pointer;
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}
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void GLStagingBuffer::QueueStagingCopy( GLBuffer* dst, const GLsizeiptr dstOffset ) {
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copyQueue[currentCopy].dst = dst;
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copyQueue[currentCopy].dstOffset = dstOffset;
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copyQueue[currentCopy].stagingOffset = last;
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copyQueue[currentCopy].size = pointer - last;
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currentCopy++;
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if ( currentCopy == MAX_COPIES ) {
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FlushStagingCopyQueue();
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}
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}
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void GLStagingBuffer::FlushStagingCopyQueue() {
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for ( GLStagingCopy& copy : copyQueue ) {
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if ( copy.dst ) {
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GLBufferCopy( &buffer, copy.dst, copy.stagingOffset, copy.dstOffset, copy.size );
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copy.dst = nullptr;
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}
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}
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currentCopy = 0;
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GL_CheckErrors();
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}
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void GLStagingBuffer::FlushAll() {
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FlushBuffer();
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FlushStagingCopyQueue();
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}
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void GLStagingBuffer::InitGLBuffer() {
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buffer.GenBuffer();
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buffer.BufferStorage( SIZE, 1, nullptr );
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buffer.MapAll();
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GL_CheckErrors();
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}
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void GLStagingBuffer::FreeGLBuffer() {
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buffer.DelBuffer();
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}

‎src/engine/renderer/GLMemory.h

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/*
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===========================================================================
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Daemon BSD Source Code
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Copyright (c) 2025 Daemon Developers
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All rights reserved.
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This file is part of the Daemon BSD Source Code (Daemon Source Code).
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Redistribution and use in source and binary forms, with or without
11+
modification, are permitted provided that the following conditions are met:
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* Redistributions of source code must retain the above copyright
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notice, this list of conditions and the following disclaimer.
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* Redistributions in binary form must reproduce the above copyright
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notice, this list of conditions and the following disclaimer in the
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documentation and/or other materials provided with the distribution.
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* Neither the name of the Daemon developers nor the
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names of its contributors may be used to endorse or promote products
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derived from this software without specific prior written permission.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
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ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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DISCLAIMED. IN NO EVENT SHALL DAEMON DEVELOPERS BE LIABLE FOR ANY
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DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
26+
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
27+
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
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ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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===========================================================================
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*/
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// GLMemory.h
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#ifndef GLMEMORY_H
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#define GLMEMORY_H
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#include "gl_shader.h"
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void GLBufferCopy( GLBuffer* src, GLBuffer* dst, GLintptr srcOffset, GLintptr dstOffset, GLsizeiptr size );
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struct GLStagingCopy {
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GLBuffer* dst;
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GLsizeiptr stagingOffset;
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GLsizeiptr dstOffset;
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GLsizeiptr size;
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};
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class GLStagingBuffer {
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public:
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uint32_t* MapBuffer( const GLsizeiptr size );
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void FlushBuffer();
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void QueueStagingCopy( GLBuffer* dst, const GLsizeiptr dstOffset );
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void FlushStagingCopyQueue();
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void FlushAll();
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void InitGLBuffer();
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void FreeGLBuffer();
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private:
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static const GLsizeiptr SIZE;
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GLsizeiptr pointer = 0;
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GLsizeiptr current = 0;
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GLsizeiptr last = 0;
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static const uint32_t MAX_COPIES = 16;
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GLStagingCopy copyQueue[MAX_COPIES];
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uint32_t currentCopy = 0;
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GLBuffer buffer = GLBuffer( "staging", BufferBind::STAGING, GL_MAP_WRITE_BIT | GL_MAP_PERSISTENT_BIT,
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GL_MAP_FLUSH_EXPLICIT_BIT | GL_MAP_INVALIDATE_BUFFER_BIT );
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};
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extern GLStagingBuffer stagingBuffer;
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#endif // GLMEMORY_H

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