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FBORenderContextProvider optimization #145

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83 changes: 75 additions & 8 deletions source/SharpGL/Core/SharpGL.WPF/OpenGLControl.xaml.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -3,6 +3,7 @@
using System.Diagnostics;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Interop;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Threading;
Expand All @@ -17,6 +18,16 @@ namespace SharpGL.WPF
/// </summary>
public partial class OpenGLControl : UserControl
{
// Fields to support the WritableBitmap method of rendering the image for display
byte[] m_imageBuffer;
WriteableBitmap m_writeableBitmap;
Int32Rect m_imageRect;
int m_imageStride;
double m_dpiX = 96;
double m_dpiY = 96;
PixelFormat m_format = PixelFormats.Bgra32;
int m_bytesPerPixel = 32 >> 3;

/// <summary>
/// Initializes a new instance of the <see cref="OpenGLControl"/> class.
/// </summary>
Expand Down Expand Up @@ -105,6 +116,8 @@ private void UpdateOpenGLControl(int width, int height)
}
}
}
// Force re-creation of image buffer since size has changed
m_imageBuffer = null;
}

/// <summary>
Expand All @@ -123,6 +136,9 @@ public override void OnApplyTemplate()
gl.Create(OpenGLVersion, RenderContextType, 1, 1, 32, null);
}

// Force re-set of dpi and format settings
m_dpiX = 0;

// Create our fast event args.
eventArgsFast = new OpenGLEventArgs(gl);

Expand Down Expand Up @@ -184,10 +200,7 @@ void timer_Tick(object sender, EventArgs e)

if (hBitmap != IntPtr.Zero)
{
var newFormatedBitmapSource = GetFormatedBitmapSource(hBitmap);

// Copy the pixels over.
image.Source = newFormatedBitmapSource;
FillImageSource(provider.DIBSection.Bits, hBitmap);
}
}
break;
Expand All @@ -202,10 +215,7 @@ void timer_Tick(object sender, EventArgs e)

if (hBitmap != IntPtr.Zero)
{
var newFormatedBitmapSource = GetFormatedBitmapSource(hBitmap);

// Copy the pixels over.
image.Source = newFormatedBitmapSource;
FillImageSource(provider.InternalDIBSection.Bits, hBitmap);
}
}
break;
Expand Down Expand Up @@ -395,5 +405,62 @@ public OpenGL OpenGL
{
get { return gl; }
}

/// Fill the ImageSource from the provided bits IntPtr, using the provided hBitMap IntPtr
/// if needed to determine key data from the bitmap source.
/// </summary>


/// <param name="bits">An IntPtr to the bits for the bitmap image. Generally provided from
/// DIBSectionRenderContextProvider.DIBSection.Bits or from
/// FBORenderContextProvider.InternalDIBSection.Bits.</param>
/// <param name="hBitmap">An IntPtr to the HBitmap for the image. Generally provided from
/// DIBSectionRenderContextProvider.DIBSection.HBitmap or from
/// FBORenderContextProvider.InternalDIBSection.HBitmap.</param>
public void FillImageSource(IntPtr bits, IntPtr hBitmap)
{
// If DPI hasn't been set, use a call to HBitmapToBitmapSource to fill the info
// This should happen only ONCE (near the start of the application)
if (m_dpiX == 0)
{
var bitmapSource = BitmapConversion.HBitmapToBitmapSource(hBitmap);
m_dpiX = bitmapSource.DpiX;
m_dpiY = bitmapSource.DpiY;
m_format = bitmapSource.Format;
m_bytesPerPixel = gl.RenderContextProvider.BitDepth >> 3;
// FBO render context flips the image vertically, so transform to compensate
if (RenderContextType == SharpGL.RenderContextType.FBO)
{
image.RenderTransform = new ScaleTransform(1.0, -1.0);
image.RenderTransformOrigin = new Point(0.0, 0.5);
}
else
{
image.RenderTransform = Transform.Identity;
image.RenderTransformOrigin = new Point(0.0, 0.0);
}
}
// If the image buffer is null, create it
// This should happen when the size of the image changes
if (m_imageBuffer == null)
{
int width = gl.RenderContextProvider.Width;
int height = gl.RenderContextProvider.Height;

int imageBufferSize = width * height * m_bytesPerPixel;
m_imageBuffer = new byte[imageBufferSize];
m_writeableBitmap = new WriteableBitmap(width, height, m_dpiX, m_dpiY, m_format, null);
m_imageRect = new Int32Rect(0, 0, width, height);
m_imageStride = width * m_bytesPerPixel;
}

// Fill the image buffer from the bits and create the writeable bitmap
System.Runtime.InteropServices.Marshal.Copy(bits, m_imageBuffer, 0, m_imageBuffer.Length);
m_writeableBitmap.WritePixels(m_imageRect, m_imageBuffer, m_imageStride, 0);

image.Source = m_writeableBitmap;
}


}
}
85 changes: 75 additions & 10 deletions source/SharpGL/Core/SharpGL/RenderContextProviders/FBORenderContextProvider.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,13 +1,17 @@
using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using SharpGL.Version;

namespace SharpGL.RenderContextProviders
{
public class FBORenderContextProvider : HiddenWindowRenderContextProvider
{
[DllImport("kernel32.dll", EntryPoint = "CopyMemory", SetLastError = false)]
public static extern void CopyMemory(IntPtr dest, IntPtr src, uint count);

/// <summary>
/// Initializes a new instance of the <see cref="FBORenderContextProvider"/> class.
/// </summary>
Expand Down Expand Up @@ -60,6 +64,14 @@ public override bool Create(OpenGLVersion openGLVersion, OpenGL gl, int width, i
gl.FramebufferRenderbufferEXT(OpenGL.GL_FRAMEBUFFER_EXT, OpenGL.GL_DEPTH_ATTACHMENT_EXT,
OpenGL.GL_RENDERBUFFER_EXT, depthRenderBufferID);


if(usePBO)
{
pboIds = new uint[PBO_COUNT];
int byte_count = width * height * 4;
CreatePBOs((uint)byte_count, pboIds);
}

dibSectionDeviceContext = Win32.CreateCompatibleDC(deviceContextHandle);

// Create the DIB section.
Expand All @@ -68,6 +80,17 @@ public override bool Create(OpenGLVersion openGLVersion, OpenGL gl, int width, i
return true;
}

private void CreatePBOs(uint byte_count, uint[] ids)
{
gl.GenBuffersARB(PBO_COUNT, pboIds);
for (int i = 0; i < PBO_COUNT; ++i)
{
gl.BindBufferARB(OpenGL.GL_PIXEL_PACK_BUFFER_ARB, ids[i]);
gl.BufferDataARB(OpenGL.GL_PIXEL_PACK_BUFFER_ARB, byte_count, (IntPtr)0, OpenGL.GL_STREAM_READ_ARB);
}
gl.BindBufferARB(OpenGL.GL_PIXEL_PACK_BUFFER_ARB, 0);
}

private void DestroyFramebuffers()
{
// Delete the render buffers.
Expand All @@ -80,6 +103,11 @@ private void DestroyFramebuffers()
colourRenderBufferID = 0;
depthRenderBufferID = 0;
frameBufferID = 0;

if (usePBO)
{
gl.DeleteBuffersARB(PBO_COUNT, pboIds);
}
}

public override void Destroy()
Expand Down Expand Up @@ -141,22 +169,53 @@ public override void SetDimensions(int width, int height)
OpenGL.GL_RENDERBUFFER_EXT, colourRenderBufferID);
gl.FramebufferRenderbufferEXT(OpenGL.GL_FRAMEBUFFER_EXT, OpenGL.GL_DEPTH_ATTACHMENT_EXT,
OpenGL.GL_RENDERBUFFER_EXT, depthRenderBufferID);

if (usePBO)
{
CreatePBOs((uint)(width * height * 4), pboIds);
}
}

public override void Blit(IntPtr hdc)
{
if (deviceContextHandle != IntPtr.Zero)
{
// Set the read buffer.
gl.ReadBuffer(OpenGL.GL_COLOR_ATTACHMENT0_EXT);

// Read the pixels into the DIB section.
gl.ReadPixels(0, 0, Width, Height, OpenGL.GL_BGRA,
OpenGL.GL_UNSIGNED_BYTE, dibSection.Bits);

// Blit the DC (containing the DIB section) to the target DC.
Win32.BitBlt(hdc, 0, 0, Width, Height,
dibSectionDeviceContext, 0, 0, Win32.SRCCOPY);
if(!usePBO)
{
// Set the read buffer.
gl.ReadBuffer(OpenGL.GL_COLOR_ATTACHMENT0_EXT);

// Read the pixels into the DIB section.
gl.ReadPixels(0, 0, Width, Height, OpenGL.GL_BGRA,
OpenGL.GL_UNSIGNED_BYTE, dibSection.Bits);

// Blit the DC (containing the DIB section) to the target DC.
Win32.BitBlt(hdc, 0, 0, Width, Height,
dibSectionDeviceContext, 0, 0, Win32.SRCCOPY);
}
else
{
uint pbo_count = (uint)PBO_COUNT;
current_pbo_index = (current_pbo_index + 1) % pbo_count;
uint nextIndex = (current_pbo_index + pbo_count - 1) % pbo_count;
// Set the read buffer.
gl.ReadBuffer(OpenGL.GL_COLOR_ATTACHMENT0_EXT);

gl.BindBufferARB(OpenGL.GL_PIXEL_PACK_BUFFER_ARB, pboIds[current_pbo_index]);
gl.ReadPixels(0, 0, Width, Height, OpenGL.GL_BGRA, OpenGL.GL_UNSIGNED_BYTE, null);

// map the PBO that contain framebuffer pixels before processing it
gl.BindBufferARB(OpenGL.GL_PIXEL_PACK_BUFFER_ARB, pboIds[nextIndex]);
IntPtr src = gl.MapBufferARB(OpenGL.GL_PIXEL_PACK_BUFFER_ARB, OpenGL.GL_READ_ONLY_ARB);

CopyMemory(dibSection.Bits, src, (uint)(Width*Height*4));

// Blit the DC (containing the DIB section) to the target DC.
Win32.BitBlt(hdc, 0, 0, Width, Height,
dibSectionDeviceContext, 0, 0, Win32.SRCCOPY);

gl.UnmapBufferARB(OpenGL.GL_PIXEL_PACK_BUFFER_ARB);
}
}
}

Expand All @@ -167,6 +226,12 @@ public override void Blit(IntPtr hdc)
protected DIBSection dibSection = new DIBSection();
protected OpenGL gl;

protected bool usePBO = false;
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@alariq alariq Mar 2, 2018

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Set this to true to enable PBO based optimization

protected int PBO_COUNT = 2;
protected uint[] pboIds;
//protected
protected uint current_pbo_index = 0;

/// <summary>
/// Gets the internal DIB section.
/// </summary>
Expand Down