Fix an intel LG warning by orphaning text memory

[ipdf/code.git] / src / graphicsbuffer.cpp

diff --git a/src/graphicsbuffer.cpp b/src/graphicsbuffer.cpp
index fe5ae1c..37d9b12 100644 (file)
--- a/src/graphicsbuffer.cpp
+++ b/src/graphicsbuffer.cpp
@@ -1,8 +1,5 @@
 #include "graphicsbuffer.h"
 #include "log.h"
-#define GL_GLEXT_PROTOTYPES
-#include <SDL_opengl.h>
-#include <GL/glext.h>
 
 using namespace IPDF;
 
@@ -72,6 +69,8 @@ GraphicsBuffer::GraphicsBuffer()
        m_map_pointer = nullptr;
        m_buffer_size = 0;
        m_buffer_shape_dirty = true;
+       m_buffer_handle = 0;
+       m_buffer_usage = BufferUsageDynamicDraw;
        SetUsage(BufferUsageStaticDraw);
 }
 
@@ -101,6 +100,11 @@ void GraphicsBuffer::SetUsage(GraphicsBuffer::BufferUsage bufUsage)
 void GraphicsBuffer::Invalidate()
 {
        m_invalidated = true;
+       if (!m_buffer_shape_dirty)
+       {
+               // Orphan the block of memory we're pointing to.
+               Upload(m_buffer_size, nullptr);
+       }
        // Apparently not supported.
        //glInvalidateBufferData(m_buffer_handle);
 }
@@ -129,7 +133,14 @@ void* GraphicsBuffer::Map(bool read, bool write, bool invalidate)
        GLenum target = BufferTypeToGLType(m_buffer_type);
 
        if (invalidate)
-              m_invalidated = true;
+       {
+               m_invalidated = true;
+
+               // Intel's Mesa driver does not rename the buffer when we map with GL_MAP_INVALIDATE_BUFFER_BIT,
+               // resulting in the CPU stalling waiting for rendering from the buffer to complete on the GPU.
+               // We manually force the buffer to be renamed here to avoid this.
+               m_buffer_shape_dirty = true;
+       }
 
        if (m_map_pointer)
                Warn("Tried to map already mapped buffer!");    
@@ -166,6 +177,7 @@ void GraphicsBuffer::UnMap()
        Bind();
        glUnmapBuffer(target);
        m_map_pointer = nullptr;
+       m_invalidated = false;
 }
 
 void GraphicsBuffer::Upload(size_t length, const void* data)
@@ -179,6 +191,8 @@ void GraphicsBuffer::Upload(size_t length, const void* data)
        
        Bind();
        glBufferData(target, length, data, usage);
+       if (data != nullptr)
+               m_invalidated = false;
        m_buffer_size = length;
 }
 
@@ -190,6 +204,7 @@ void GraphicsBuffer::UploadRange(size_t length, intptr_t offset, const void* dat
        
        Bind();
        glBufferSubData(target, offset, length, data);
+       m_invalidated = false;
 }
 
 void GraphicsBuffer::Resize(size_t length)
@@ -214,7 +229,7 @@ void GraphicsBuffer::Resize(size_t length)
        }
 }
 
-void GraphicsBuffer::Bind()
+void GraphicsBuffer::Bind() const
 {
        if (m_buffer_type == BufferTypeUniform)
                glBindBufferBase(GL_UNIFORM_BUFFER, 0, m_buffer_handle);