/Open Model Implementation/ColladaViewer/GraphicsDeviceControl.cs
C# | 302 lines | 157 code | 66 blank | 79 comment | 9 complexity | d1f9b9146a35a6bf9b7dc569edd9da24 MD5 | raw file
- using System;
- using System.Collections.Generic;
- using System.Drawing;
- using System.Linq;
- using System.Text;
- using System.Windows.Forms;
- using Microsoft.Xna.Framework.Graphics;
-
- namespace ColladaViewer
- {
- // System.Drawing and the XNA Framework both define Color and Rectangle
- // types. To avoid conflicts, we specify exactly which ones to use.
- using Color = System.Drawing.Color;
- using Rectangle = Microsoft.Xna.Framework.Rectangle;
-
-
- /// <summary>
- /// Custom control uses the XNA Framework GraphicsDevice to render onto
- /// a Windows Form. Derived classes can override the Initialize and Draw
- /// methods to add their own drawing code.
- /// </summary>
- abstract public class GraphicsDeviceControl : Control
- {
- #region Fields
-
-
- // However many GraphicsDeviceControl instances you have, they all share
- // the same underlying GraphicsDevice, managed by this helper service.
- GraphicsDeviceService graphicsDeviceService;
-
-
- #endregion
-
- #region Properties
-
-
- /// <summary>
- /// Gets a GraphicsDevice that can be used to draw onto this control.
- /// </summary>
- public GraphicsDevice GraphicsDevice
- {
- get { return graphicsDeviceService.GraphicsDevice; }
- }
-
-
- /// <summary>
- /// Gets an IServiceProvider containing our IGraphicsDeviceService.
- /// This can be used with components such as the ContentManager,
- /// which use this service to look up the GraphicsDevice.
- /// </summary>
- public ServiceContainer Services
- {
- get { return services; }
- }
-
- ServiceContainer services = new ServiceContainer();
-
-
- #endregion
-
- #region Initialization
-
-
- /// <summary>
- /// Initializes the control.
- /// </summary>
- protected override void OnCreateControl()
- {
- // Don't initialize the graphics device if we are running in the designer.
- if (!DesignMode)
- {
- try
- {
- graphicsDeviceService = GraphicsDeviceService.AddRef(Handle,
- ClientSize.Width,
- ClientSize.Height);
-
- // Register the service, so components like ContentManager can find it.
- services.AddService<IGraphicsDeviceService>(graphicsDeviceService);
-
- // Give derived classes a chance to initialize themselves.
- Initialize();
- }
- catch (Exception ex)
- {
- throw new Exception("Graphics Device Service could not be created");
- }
- }
-
- base.OnCreateControl();
- }
-
-
- /// <summary>
- /// Disposes the control.
- /// </summary>
- protected override void Dispose(bool disposing)
- {
- if (graphicsDeviceService != null)
- {
- graphicsDeviceService.Release(disposing);
- graphicsDeviceService = null;
- }
-
- base.Dispose(disposing);
- }
-
-
- #endregion
-
- #region Paint
-
-
- /// <summary>
- /// Redraws the control in response to a WinForms paint message.
- /// </summary>
- protected override void OnPaint(PaintEventArgs e)
- {
- string beginDrawError = BeginDraw();
-
- if (string.IsNullOrEmpty(beginDrawError))
- {
- // Draw the control using the GraphicsDevice.
- Draw();
- EndDraw();
- }
- else
- {
- // If BeginDraw failed, show an error message using System.Drawing.
- PaintUsingSystemDrawing(e.Graphics, beginDrawError);
- }
- }
-
-
- /// <summary>
- /// Attempts to begin drawing the control. Returns an error message string
- /// if this was not possible, which can happen if the graphics device is
- /// lost, or if we are running inside the Form designer.
- /// </summary>
- string BeginDraw()
- {
- // If we have no graphics device, we must be running in the designer.
- if (graphicsDeviceService == null)
- {
- return Text + "\n\n" + GetType();
- }
-
- // Make sure the graphics device is big enough, and is not lost.
- string deviceResetError = HandleDeviceReset();
-
- if (!string.IsNullOrEmpty(deviceResetError))
- {
- return deviceResetError;
- }
-
- // Many GraphicsDeviceControl instances can be sharing the same
- // GraphicsDevice. The device backbuffer will be resized to fit the
- // largest of these controls. But what if we are currently drawing
- // a smaller control? To avoid unwanted stretching, we set the
- // viewport to only use the top left portion of the full backbuffer.
- Viewport viewport = new Viewport();
-
- viewport.X = 0;
- viewport.Y = 0;
-
- viewport.Width = ClientSize.Width;
- viewport.Height = ClientSize.Height;
-
- viewport.MinDepth = 0;
- viewport.MaxDepth = 1;
-
- GraphicsDevice.Viewport = viewport;
-
- return null;
- }
-
-
- /// <summary>
- /// Ends drawing the control. This is called after derived classes
- /// have finished their Draw method, and is responsible for presenting
- /// the finished image onto the screen, using the appropriate WinForms
- /// control handle to make sure it shows up in the right place.
- /// </summary>
- void EndDraw()
- {
- try
- {
- Rectangle sourceRectangle = new Rectangle(0, 0, ClientSize.Width,
- ClientSize.Height);
-
- GraphicsDevice.Present(sourceRectangle, null, this.Handle);
- }
- catch
- {
- // Present might throw if the device became lost while we were
- // drawing. The lost device will be handled by the next BeginDraw,
- // so we just swallow the exception.
- }
- }
-
-
- /// <summary>
- /// Helper used by BeginDraw. This checks the graphics device status,
- /// making sure it is big enough for drawing the current control, and
- /// that the device is not lost. Returns an error string if the device
- /// could not be reset.
- /// </summary>
- string HandleDeviceReset()
- {
- bool deviceNeedsReset = false;
-
- switch (GraphicsDevice.GraphicsDeviceStatus)
- {
- case GraphicsDeviceStatus.Lost:
- // If the graphics device is lost, we cannot use it at all.
- return "Graphics device lost";
-
- case GraphicsDeviceStatus.NotReset:
- // If device is in the not-reset state, we should try to reset it.
- deviceNeedsReset = true;
- break;
-
- default:
- // If the device state is ok, check whether it is big enough.
- PresentationParameters pp = GraphicsDevice.PresentationParameters;
-
- deviceNeedsReset = (ClientSize.Width > pp.BackBufferWidth) ||
- (ClientSize.Height > pp.BackBufferHeight);
- break;
- }
-
- // Do we need to reset the device?
- if (deviceNeedsReset)
- {
- try
- {
- graphicsDeviceService.ResetDevice(ClientSize.Width,
- ClientSize.Height);
- }
- catch (Exception e)
- {
- return "Graphics device reset failed\n\n" + e;
- }
- }
-
- return null;
- }
-
-
- /// <summary>
- /// If we do not have a valid graphics device (for instance if the device
- /// is lost, or if we are running inside the Form designer), we must use
- /// regular System.Drawing method to display a status message.
- /// </summary>
- protected virtual void PaintUsingSystemDrawing(Graphics graphics, string text)
- {
- graphics.Clear(Color.CornflowerBlue);
-
- using (Brush brush = new SolidBrush(Color.Black))
- {
- using (StringFormat format = new StringFormat())
- {
- format.Alignment = StringAlignment.Center;
- format.LineAlignment = StringAlignment.Center;
-
- graphics.DrawString(text, Font, brush, ClientRectangle, format);
- }
- }
- }
-
-
- /// <summary>
- /// Ignores WinForms paint-background messages. The default implementation
- /// would clear the control to the current background color, causing
- /// flickering when our OnPaint implementation then immediately draws some
- /// other color over the top using the XNA Framework GraphicsDevice.
- /// </summary>
- protected override void OnPaintBackground(PaintEventArgs pevent)
- {
- }
-
-
- #endregion
-
- #region Abstract Methods
-
-
- /// <summary>
- /// Derived classes override this to initialize their drawing code.
- /// </summary>
- protected abstract void Initialize();
-
-
- /// <summary>
- /// Derived classes override this to draw themselves using the GraphicsDevice.
- /// </summary>
- protected abstract void Draw();
-
-
- #endregion
- }
- }