//--------------------------------------------------------------
#region Methods
//--------------------------------------------------------------
/// <summary>
/// Computes the intersection of <see cref="MeshNode"/>s.
/// </summary>
/// <param name="meshNodePairs">
/// A collection of <see cref="MeshNode"/> pairs.The renderer computes the intersection volume
/// of each pair.
/// </param>
/// <param name="color">The diffuse color used for the intersection.</param>
/// <param name="alpha">The opacity of the intersection.</param>
/// <param name="maxConvexity">
/// The maximum convexity of the submeshes. A convex mesh has a convexity of 1. A concave mesh
/// has a convexity greater than 1. Convexity is the number of layers required for depth peeling
/// (= the number of front face layers when looking at the object).
/// </param>
/// <param name="context">The render context.</param>
/// <remarks>
/// <para>
/// This method renders an off-screen image (color and depth) of the intersection volume. This
/// operation destroys the currently set render target and depth/stencil buffer.
/// </para>
/// </remarks>
/// <exception cref="ObjectDisposedException">
/// The <see cref="IntersectionRenderer"/> has already been disposed.
/// </exception>
/// <exception cref="ArgumentNullException">
/// <paramref name="meshNodePairs"/> or <see cref="context"/> is
/// <see langword="null"/>.
/// </exception>
/// <exception cref="ArgumentOutOfRangeException">
/// The convexity must be greater than 0.
/// </exception>
/// <exception cref="GraphicsException">
/// Invalid render context: Graphics service is not set.
/// </exception>
/// <exception cref="GraphicsException">
/// Invalid render context: Wrong graphics device.
/// </exception>
/// <exception cref="GraphicsException">
/// Invalid render context: Scene is not set.
/// </exception>
/// <exception cref="GraphicsException">
/// Invalid render context: Camera node needs to be set in render context.
/// </exception>
public void ComputeIntersection(IEnumerable <Pair <MeshNode> > meshNodePairs,
Vector3F color, float alpha, float maxConvexity, RenderContext context)
{
if (_isDisposed)
{
throw new ObjectDisposedException("IntersectionRenderer has already been disposed.");
}
if (meshNodePairs == null)
{
throw new ArgumentNullException("meshNodePairs");
}
if (maxConvexity < 1)
{
throw new ArgumentOutOfRangeException("maxConvexity", "The max convexity must be greater than 0.");
}
if (context == null)
{
throw new ArgumentNullException("context");
}
if (context.GraphicsService == null)
{
throw new GraphicsException("Invalid render context: Graphics service is not set.");
}
if (_graphicsService != context.GraphicsService)
{
throw new GraphicsException("Invalid render context: Wrong graphics service.");
}
if (context.CameraNode == null)
{
throw new GraphicsException("Camera node needs to be set in render context.");
}
if (context.Scene == null)
{
throw new GraphicsException("A scene needs to be set in the render context.");
}
// Create 2 ordered pairs for each unordered pair.
_pairs.Clear();
foreach (var pair in meshNodePairs)
{
if (pair.First == null || pair.Second == null)
{
continue;
}
// Frustum culling.
if (!context.Scene.HaveContact(pair.First, context.CameraNode))
{
continue;
}
if (!context.Scene.HaveContact(pair.Second, context.CameraNode))
{
continue;
}
_pairs.Add(new Pair <MeshNode, MeshNode>(pair.First, pair.Second));
_pairs.Add(new Pair <MeshNode, MeshNode>(pair.Second, pair.First));
}
var renderTargetPool = _graphicsService.RenderTargetPool;
if (_pairs.Count == 0)
{
renderTargetPool.Recycle(_intersectionImage);
_intersectionImage = null;
return;
}
// Color and alpha are applied in RenderIntersection().
_color = color;
_alpha = alpha;
var graphicsDevice = _graphicsService.GraphicsDevice;
// Save original render states.
var originalBlendState = graphicsDevice.BlendState;
var originalDepthStencilState = graphicsDevice.DepthStencilState;
var originalRasterizerState = graphicsDevice.RasterizerState;
var originalScissorRectangle = graphicsDevice.ScissorRectangle;
// Get offscreen render targets.
var viewport = context.Viewport;
viewport.X = 0;
viewport.Y = 0;
viewport.Width = (int)(viewport.Width / DownsampleFactor);
viewport.Height = (int)(viewport.Height / DownsampleFactor);
var renderTargetFormat = new RenderTargetFormat(viewport.Width, viewport.Height, false, SurfaceFormat.Color, DepthFormat.Depth24Stencil8);
// Try to reuse any existing render targets.
// (Usually they are recycled in RenderIntersection()).
var currentScene = _intersectionImage;
if (currentScene == null || !renderTargetFormat.IsCompatibleWith(currentScene))
{
currentScene.SafeDispose();
currentScene = renderTargetPool.Obtain2D(renderTargetFormat);
}
var lastScene = renderTargetPool.Obtain2D(renderTargetFormat);
// Set shared effect parameters.
var cameraNode = context.CameraNode;
var view = (Matrix)cameraNode.View;
var projection = cameraNode.Camera.Projection;
var near = projection.Near;
var far = projection.Far;
_parameterViewportSize.SetValue(new Vector2(viewport.Width, viewport.Height));
// The DepthEpsilon has to be tuned if depth peeling does not work because
// of numerical problems equality z comparisons.
_parameterCameraParameters.SetValue(new Vector3(near, far - near, 0.0000001f));
_parameterView.SetValue(view);
_parameterProjection.SetValue((Matrix)projection);
var defaultTexture = _graphicsService.GetDefaultTexture2DBlack();
// Handle all pairs.
bool isFirstPass = true;
while (true)
{
// Find a mesh node A and all mesh nodes to which it needs to be clipped.
MeshNode meshNodeA = null;
_partners.Clear();
for (int i = 0; i < _pairs.Count; i++)
{
var pair = _pairs[i];
if (pair.First == null)
{
continue;
}
if (meshNodeA == null)
{
meshNodeA = pair.First;
}
if (pair.First == meshNodeA)
{
_partners.Add(pair.Second);
// Remove this pair.
_pairs[i] = new Pair <MeshNode, MeshNode>();
}
}
// Abort if we have handled all pairs.
if (meshNodeA == null)
{
break;
}
var worldTransformA = (Matrix)(meshNodeA.PoseWorld * Matrix44F.CreateScale(meshNodeA.ScaleWorld));
if (EnableScissorTest)
{
// Scissor rectangle of A.
var scissorA = GraphicsHelper.GetScissorRectangle(context.CameraNode, viewport, meshNodeA);
// Union of scissor rectangles of partners.
Rectangle partnerRectangle = GraphicsHelper.GetScissorRectangle(context.CameraNode, viewport, _partners[0]);
for (int i = 1; i < _partners.Count; i++)
{
var a = GraphicsHelper.GetScissorRectangle(context.CameraNode, viewport, _partners[i]);
partnerRectangle = Rectangle.Union(partnerRectangle, a);
}
// Use intersection of A and partners.
graphicsDevice.ScissorRectangle = Rectangle.Intersect(scissorA, partnerRectangle);
// We store the union of all scissor rectangles for use in RenderIntersection().
if (isFirstPass)
{
_totalScissorRectangle = graphicsDevice.ScissorRectangle;
}
else
{
_totalScissorRectangle = Rectangle.Union(_totalScissorRectangle, graphicsDevice.ScissorRectangle);
}
}
// Depth peeling of A.
for (int layer = 0; layer < maxConvexity; layer++)
{
// Set and clear render target.
graphicsDevice.SetRenderTarget(currentScene);
graphicsDevice.Clear(new Color(1, 1, 1, 0)); // RGB = "a large depth", A = "empty area"
// Render a depth layer of A.
graphicsDevice.DepthStencilState = DepthStencilStateWriteLess;
graphicsDevice.BlendState = BlendState.Opaque;
graphicsDevice.RasterizerState = EnableScissorTest ? CullCounterClockwiseScissor : RasterizerState.CullCounterClockwise;
_parameterWorld.SetValue(worldTransformA);
_parameterTexture.SetValue((layer == 0) ? defaultTexture : lastScene);
_passPeel.Apply();
foreach (var submesh in meshNodeA.Mesh.Submeshes)
{
submesh.Draw();
}
// Render partners to set stencil.
graphicsDevice.DepthStencilState = DepthStencilStateOnePassStencilFail;
graphicsDevice.BlendState = BlendStateNoWrite;
graphicsDevice.RasterizerState = EnableScissorTest ? CullNoneScissor : RasterizerState.CullNone;
foreach (var partner in _partners)
{
_parameterWorld.SetValue((Matrix)(partner.PoseWorld * Matrix44F.CreateScale(partner.ScaleWorld)));
_passMark.Apply();
foreach (var submesh in partner.Mesh.Submeshes)
{
submesh.Draw();
}
}
// Clear depth buffer. Leave stencil buffer unchanged.
graphicsDevice.Clear(ClearOptions.DepthBuffer, new Color(0, 1, 0), 1, 0);
// Render A to compute lighting.
graphicsDevice.DepthStencilState = DepthStencilStateStencilNotEqual0;
graphicsDevice.BlendState = BlendState.Opaque;
graphicsDevice.RasterizerState = EnableScissorTest ? CullCounterClockwiseScissor : RasterizerState.CullCounterClockwise;
_parameterWorld.SetValue(worldTransformA);
_passDraw.Apply();
foreach (var submesh in meshNodeA.Mesh.Submeshes)
{
submesh.Draw();
}
// Combine last intersection image with current.
if (!isFirstPass)
{
graphicsDevice.DepthStencilState = DepthStencilState.DepthRead;
graphicsDevice.BlendState = BlendState.Opaque;
graphicsDevice.RasterizerState = EnableScissorTest ? CullNoneScissor : RasterizerState.CullNone;
_parameterTexture.SetValue(lastScene);
_passCombine.Apply();
graphicsDevice.DrawFullScreenQuad();
}
isFirstPass = false;
// ----- Swap render targets.
MathHelper.Swap(ref lastScene, ref currentScene);
}
}
// Store final images for RenderIntersection.
_intersectionImage = lastScene;
// Scale scissor rectangle back to full-screen resolution.
if (DownsampleFactor > 1)
{
_totalScissorRectangle.X = (int)(_totalScissorRectangle.X * DownsampleFactor);
_totalScissorRectangle.Y = (int)(_totalScissorRectangle.Y * DownsampleFactor);
_totalScissorRectangle.Width = (int)(_totalScissorRectangle.Width * DownsampleFactor);
_totalScissorRectangle.Height = (int)(_totalScissorRectangle.Height * DownsampleFactor);
}
// Restore original render state.
graphicsDevice.BlendState = originalBlendState ?? BlendState.Opaque;
graphicsDevice.DepthStencilState = originalDepthStencilState ?? DepthStencilState.Default;
graphicsDevice.RasterizerState = originalRasterizerState ?? RasterizerState.CullCounterClockwise;
graphicsDevice.ScissorRectangle = originalScissorRectangle;
renderTargetPool.Recycle(currentScene);
_partners.Clear();
_pairs.Clear();
}
//--------------------------------------------------------------
#region Methods
//--------------------------------------------------------------
/// <summary>
/// Computes the intersection of <see cref="MeshNode"/>s.
/// </summary>
/// <param name="meshNodePairs">
/// A collection of <see cref="MeshNode"/> pairs.The renderer computes the intersection volume
/// of each pair.
/// </param>
/// <param name="color">The diffuse color used for the intersection.</param>
/// <param name="alpha">The opacity of the intersection.</param>
/// <param name="maxConvexity">
/// The maximum convexity of the submeshes. A convex mesh has a convexity of 1. A concave mesh
/// has a convexity greater than 1. Convexity is the number of layers required for depth peeling
/// (= the number of front face layers when looking at the object).
/// </param>
/// <param name="context">The render context.</param>
/// <remarks>
/// <para>
/// This method renders an off-screen image (color and depth) of the intersection volume. This
/// operation destroys the currently set render target and depth/stencil buffer.
/// </para>
/// </remarks>
/// <exception cref="ObjectDisposedException">
/// The <see cref="IntersectionRenderer"/> has already been disposed.
/// </exception>
/// <exception cref="ArgumentNullException">
/// <paramref name="meshNodePairs"/> or <see cref="context"/> is
/// <see langword="null"/>.
/// </exception>
/// <exception cref="ArgumentOutOfRangeException">
/// The convexity must be greater than 0.
/// </exception>
/// <exception cref="GraphicsException">
/// Invalid render context: Graphics service is not set.
/// </exception>
/// <exception cref="GraphicsException">
/// Invalid render context: Wrong graphics device.
/// </exception>
/// <exception cref="GraphicsException">
/// Invalid render context: Scene is not set.
/// </exception>
/// <exception cref="GraphicsException">
/// Invalid render context: Camera node needs to be set in render context.
/// </exception>
public void ComputeIntersection(IEnumerable<Pair<MeshNode>> meshNodePairs,
Vector3F color, float alpha, float maxConvexity, RenderContext context)
{
if (_isDisposed)
throw new ObjectDisposedException("IntersectionRenderer has already been disposed.");
if (meshNodePairs == null)
throw new ArgumentNullException("meshNodePairs");
if (maxConvexity < 1)
throw new ArgumentOutOfRangeException("maxConvexity", "The max convexity must be greater than 0.");
if (context == null)
throw new ArgumentNullException("context");
if (context.GraphicsService == null)
throw new GraphicsException("Invalid render context: Graphics service is not set.");
if (_graphicsService != context.GraphicsService)
throw new GraphicsException("Invalid render context: Wrong graphics service.");
if (context.CameraNode == null)
throw new GraphicsException("Camera node needs to be set in render context.");
if (context.Scene == null)
throw new GraphicsException("A scene needs to be set in the render context.");
// Create 2 ordered pairs for each unordered pair.
_pairs.Clear();
foreach (var pair in meshNodePairs)
{
if (pair.First == null || pair.Second == null)
continue;
// Frustum culling.
if (!context.Scene.HaveContact(pair.First, context.CameraNode))
continue;
if (!context.Scene.HaveContact(pair.Second, context.CameraNode))
continue;
_pairs.Add(new Pair<MeshNode, MeshNode>(pair.First, pair.Second));
_pairs.Add(new Pair<MeshNode, MeshNode>(pair.Second, pair.First));
}
var renderTargetPool = _graphicsService.RenderTargetPool;
if (_pairs.Count == 0)
{
renderTargetPool.Recycle(_intersectionImage);
_intersectionImage = null;
return;
}
// Color and alpha are applied in RenderIntersection().
_color = color;
_alpha = alpha;
var graphicsDevice = _graphicsService.GraphicsDevice;
// Save original render states.
var originalBlendState = graphicsDevice.BlendState;
var originalDepthStencilState = graphicsDevice.DepthStencilState;
var originalRasterizerState = graphicsDevice.RasterizerState;
var originalScissorRectangle = graphicsDevice.ScissorRectangle;
// Get offscreen render targets.
var viewport = context.Viewport;
viewport.X = 0;
viewport.Y = 0;
viewport.Width = (int)(viewport.Width / DownsampleFactor);
viewport.Height = (int)(viewport.Height / DownsampleFactor);
var renderTargetFormat = new RenderTargetFormat(viewport.Width, viewport.Height, false, SurfaceFormat.Color, DepthFormat.Depth24Stencil8);
// Try to reuse any existing render targets.
// (Usually they are recycled in RenderIntersection()).
var currentScene = _intersectionImage;
if (currentScene == null || !renderTargetFormat.IsCompatibleWith(currentScene))
{
currentScene.SafeDispose();
currentScene = renderTargetPool.Obtain2D(renderTargetFormat);
}
var lastScene = renderTargetPool.Obtain2D(renderTargetFormat);
// Set shared effect parameters.
var cameraNode = context.CameraNode;
var view = (Matrix)cameraNode.View;
var projection = cameraNode.Camera.Projection;
var near = projection.Near;
var far = projection.Far;
_parameterViewportSize.SetValue(new Vector2(viewport.Width, viewport.Height));
// The DepthEpsilon has to be tuned if depth peeling does not work because
// of numerical problems equality z comparisons.
_parameterCameraParameters.SetValue(new Vector3(near, far - near, 0.0000001f));
_parameterView.SetValue(view);
_parameterProjection.SetValue((Matrix)projection);
var defaultTexture = _graphicsService.GetDefaultTexture2DBlack();
// Handle all pairs.
bool isFirstPass = true;
while (true)
{
// Find a mesh node A and all mesh nodes to which it needs to be clipped.
MeshNode meshNodeA = null;
_partners.Clear();
for (int i = 0; i < _pairs.Count; i++)
{
var pair = _pairs[i];
if (pair.First == null)
continue;
if (meshNodeA == null)
meshNodeA = pair.First;
if (pair.First == meshNodeA)
{
_partners.Add(pair.Second);
// Remove this pair.
_pairs[i] = new Pair<MeshNode, MeshNode>();
}
}
// Abort if we have handled all pairs.
if (meshNodeA == null)
break;
var worldTransformA = (Matrix)(meshNodeA.PoseWorld * Matrix44F.CreateScale(meshNodeA.ScaleWorld));
if (EnableScissorTest)
{
// Scissor rectangle of A.
var scissorA = GraphicsHelper.GetScissorRectangle(context.CameraNode, viewport, meshNodeA);
// Union of scissor rectangles of partners.
Rectangle partnerRectangle = GraphicsHelper.GetScissorRectangle(context.CameraNode, viewport, _partners[0]);
for (int i = 1; i < _partners.Count; i++)
{
var a = GraphicsHelper.GetScissorRectangle(context.CameraNode, viewport, _partners[i]);
partnerRectangle = Rectangle.Union(partnerRectangle, a);
}
// Use intersection of A and partners.
graphicsDevice.ScissorRectangle = Rectangle.Intersect(scissorA, partnerRectangle);
// We store the union of all scissor rectangles for use in RenderIntersection().
if (isFirstPass)
_totalScissorRectangle = graphicsDevice.ScissorRectangle;
else
_totalScissorRectangle = Rectangle.Union(_totalScissorRectangle, graphicsDevice.ScissorRectangle);
}
// Depth peeling of A.
for (int layer = 0; layer < maxConvexity; layer++)
{
// Set and clear render target.
graphicsDevice.SetRenderTarget(currentScene);
graphicsDevice.Clear(new Color(1, 1, 1, 0)); // RGB = "a large depth", A = "empty area"
// Render a depth layer of A.
graphicsDevice.DepthStencilState = DepthStencilStateWriteLess;
graphicsDevice.BlendState = BlendState.Opaque;
graphicsDevice.RasterizerState = EnableScissorTest ? CullCounterClockwiseScissor : RasterizerState.CullCounterClockwise;
_parameterWorld.SetValue(worldTransformA);
_parameterTexture.SetValue((layer == 0) ? defaultTexture : lastScene);
_passPeel.Apply();
foreach (var submesh in meshNodeA.Mesh.Submeshes)
submesh.Draw();
// Render partners to set stencil.
graphicsDevice.DepthStencilState = DepthStencilStateOnePassStencilFail;
graphicsDevice.BlendState = BlendStateNoWrite;
graphicsDevice.RasterizerState = EnableScissorTest ? CullNoneScissor : RasterizerState.CullNone;
foreach (var partner in _partners)
{
_parameterWorld.SetValue((Matrix)(partner.PoseWorld * Matrix44F.CreateScale(partner.ScaleWorld)));
_passMark.Apply();
foreach (var submesh in partner.Mesh.Submeshes)
submesh.Draw();
}
// Clear depth buffer. Leave stencil buffer unchanged.
graphicsDevice.Clear(ClearOptions.DepthBuffer, new Color(0, 1, 0), 1, 0);
// Render A to compute lighting.
graphicsDevice.DepthStencilState = DepthStencilStateStencilNotEqual0;
graphicsDevice.BlendState = BlendState.Opaque;
graphicsDevice.RasterizerState = EnableScissorTest ? CullCounterClockwiseScissor : RasterizerState.CullCounterClockwise;
_parameterWorld.SetValue(worldTransformA);
_passDraw.Apply();
foreach (var submesh in meshNodeA.Mesh.Submeshes)
submesh.Draw();
// Combine last intersection image with current.
if (!isFirstPass)
{
graphicsDevice.DepthStencilState = DepthStencilState.DepthRead;
graphicsDevice.BlendState = BlendState.Opaque;
graphicsDevice.RasterizerState = EnableScissorTest ? CullNoneScissor : RasterizerState.CullNone;
_parameterTexture.SetValue(lastScene);
_passCombine.Apply();
graphicsDevice.DrawFullScreenQuad();
}
isFirstPass = false;
// ----- Swap render targets.
MathHelper.Swap(ref lastScene, ref currentScene);
}
}
// Store final images for RenderIntersection.
_intersectionImage = lastScene;
// Scale scissor rectangle back to full-screen resolution.
if (DownsampleFactor > 1)
{
_totalScissorRectangle.X = (int)(_totalScissorRectangle.X * DownsampleFactor);
_totalScissorRectangle.Y = (int)(_totalScissorRectangle.Y * DownsampleFactor);
_totalScissorRectangle.Width = (int)(_totalScissorRectangle.Width * DownsampleFactor);
_totalScissorRectangle.Height = (int)(_totalScissorRectangle.Height * DownsampleFactor);
}
// Restore original render state.
graphicsDevice.BlendState = originalBlendState ?? BlendState.Opaque;
graphicsDevice.DepthStencilState = originalDepthStencilState ?? DepthStencilState.Default;
graphicsDevice.RasterizerState = originalRasterizerState ?? RasterizerState.CullCounterClockwise;
graphicsDevice.ScissorRectangle = originalScissorRectangle;
renderTargetPool.Recycle(currentScene);
_partners.Clear();
_pairs.Clear();
}
