C# RenderContext.IsPicking方法代码示例

        /// <summary>
        /// Draw this effect mesh.
        /// </summary>
        public void Draw(RenderContext context)
        {
            // Retrieve effect parameters
            var graphicsDevice = context.GraphicsDevice;
            var mesh = Mesh;
            var currentRenderData = mesh.Draw;
            var material = Material;
            var vao = vertexArrayObject;
            var drawCount = currentRenderData.DrawCount;
            var primitiveType = currentRenderData.PrimitiveType;

            parameters.Set(TransformationKeys.World, WorldMatrix);

            // TODO: We should clarify exactly how to override rasterizer states. Currently setup here on Context.Parameters to allow Material/ModelComponent overrides, but this is ugly
            // Apply rasterizer
            var rasterizer = RasterizerState; 
            if (!ForceRasterizer && Material.CullMode.HasValue && Material.CullMode.Value != RasterizerState.Description.CullMode)
            {
                switch (Material.CullMode.Value)
                {
                    case CullMode.Back:
                        rasterizer = graphicsDevice.RasterizerStates.CullBack;
                        break;
                    case CullMode.Front:
                        rasterizer = graphicsDevice.RasterizerStates.CullFront;
                        break;
                    case CullMode.None:
                        rasterizer = graphicsDevice.RasterizerStates.CullNone;
                        break;
                }
            }
            context.Parameters.Set(Effect.RasterizerStateKey, rasterizer);

            // Handle picking
            if (context.IsPicking()) // TODO move this code corresponding to picking outside of the runtime code!
            {
                parameters.Set(ModelComponentPickingShaderKeys.ModelComponentId, new Color4(RuntimeIdHelper.ToRuntimeId(RenderModel.ModelComponent)));
                parameters.Set(ModelComponentPickingShaderKeys.MeshId, new Color4(RenderModel.ModelComponent.Model.Meshes.IndexOf(Mesh)));
                parameters.Set(ModelComponentPickingShaderKeys.MaterialId, new Color4(Mesh.MaterialIndex));

                // Don't use the materials blend state on picking targets
                parameters.Set(Effect.BlendStateKey, null);
            }

            if (material != null && material.TessellationMethod != XenkoTessellationMethod.None)
            {
                var tessellationMethod = material.TessellationMethod;

                // adapt the primitive type and index buffer to the tessellation used
                if (tessellationMethod.PerformsAdjacentEdgeAverage())
                {
                    vao = GetOrCreateVertexArrayObjectAEN(context);
                    drawCount = 12 / 3 * drawCount;
                }
                primitiveType = tessellationMethod.GetPrimitiveType();
            }

            //using (Profiler.Begin(ProfilingKeys.PrepareMesh))
            {
                // Order of application of parameters:
                // - RenderPass.Parameters
                // - ModelComponent.Parameters
                // - RenderMesh.Parameters (originally copied from mesh parameters)
                // The order is based on the granularity level of each element and how shared it can be. Material is heavily shared, a model contains many meshes. An renderMesh is unique.
                // TODO: really copy mesh parameters into renderMesh instead of just referencing the meshDraw parameters.

                //var modelComponent = RenderModel.ModelComponent;
                //var hasModelComponentParams = modelComponent != null && modelComponent.Parameters != null;
                
                //var materialParameters = material != null && material.Parameters != null ? material.Parameters : null;

                parameterCollections.Clear();

                parameterCollections.Add(context.Parameters);
                FillParameterCollections(ref parameterCollections);

                // Check if we need to recreate the EffectParameterCollectionGroup
                // TODO: We can improve performance by redesigning FillParameterCollections to avoid ArrayExtensions.ArraysReferenceEqual (or directly check the appropriate parameter collections)
                // This also happens in another place: DynamicEffectCompiler (we probably want to factorize it when doing additional optimizations)
                if (parameterCollectionGroup == null || parameterCollectionGroup.Effect != Effect || !ArrayExtensions.ArraysReferenceEqual(ref previousParameterCollections, ref parameterCollections))
                {
                    previousParameterCollections.Clear();
                    previousParameterCollections.AddRange(parameterCollections);
                    parameterCollectionGroup = new EffectParameterCollectionGroup(context.GraphicsDevice, Effect, previousParameterCollections.Count, previousParameterCollections.Items);
                }

                Effect.Apply(context.GraphicsDevice, parameterCollectionGroup, true);
            }

            //using (Profiler.Begin(ProfilingKeys.RenderMesh))
            {
                if (currentRenderData != null)
                {
                    graphicsDevice.SetVertexArrayObject(vao);

                    if (currentRenderData.IndexBuffer == null)
                    {
//.........这里部分代码省略.........

        protected override void DrawCore(RenderContext context, RenderItemCollection renderItems, int fromIndex, int toIndex)
        {
            var viewParameters = context.Parameters;

            var device = context.GraphicsDevice;
            var viewInverse = Matrix.Invert(viewParameters.Get(TransformationKeys.View));
            var viewProjection = viewParameters.Get(TransformationKeys.ViewProjection);

            BlendState previousBlendState = null;
            DepthStencilState previousDepthStencilState= null;
            Effect previousEffect = null;

            var isPicking = context.IsPicking();

            bool hasBegin = false;
            for (var i = fromIndex; i <= toIndex; i++)
            {
                var renderItem = renderItems[i];
                var spriteState = (SpriteProcessor.SpriteComponentState)renderItem.DrawContext;
                var spriteComp = spriteState.SpriteComponent;
                var transfoComp = spriteState.TransformComponent;
                var depthStencilState = spriteState.SpriteComponent.IgnoreDepth ? device.DepthStencilStates.None : device.DepthStencilStates.Default;

                var sprite = spriteComp.CurrentSprite;
                if (sprite == null)
                    continue;

                // Update the sprite batch
                var blendState = isPicking ? device.BlendStates.Opaque : renderItems.HasTransparency ? (spriteComp.PremultipliedAlpha ? device.BlendStates.AlphaBlend : device.BlendStates.NonPremultiplied) : device.BlendStates.Opaque;
                var currentEffect = isPicking? GetOrCreatePickingSpriteEffect(): spriteComp.Tags.Get(IsEntitySelected)? GetOrCreateSelectedSpriteEffect(): null; // TODO remove this code when material are available
                if (previousEffect != currentEffect || blendState != previousBlendState || depthStencilState != previousDepthStencilState)
                {
                    if (hasBegin)
                    {
                        sprite3DBatch.End();
                    }
                    sprite3DBatch.Begin(viewProjection, SpriteSortMode.Deferred, blendState, null, depthStencilState, device.RasterizerStates.CullNone, currentEffect);
                    hasBegin = true;
                }
                previousEffect = currentEffect;
                previousBlendState = blendState;
                previousDepthStencilState = depthStencilState;

                var sourceRegion = sprite.Region; 
                var texture = sprite.Texture;
                var color = spriteComp.Color;
                if (isPicking) // TODO move this code corresponding to picking out of the runtime code.
                    color = new Color4(RuntimeIdHelper.ToRuntimeId(spriteComp));

                // skip the sprite if no texture is set.
                if (texture == null)
                    continue;
                
                // determine the element world matrix depending on the type of sprite
                var worldMatrix = transfoComp.WorldMatrix;
                if (spriteComp.SpriteType == SpriteType.Billboard)
                {
                    worldMatrix = viewInverse;

                    // remove scale of the camera
                    worldMatrix.Row1 /= ((Vector3)viewInverse.Row1).Length();
                    worldMatrix.Row2 /= ((Vector3)viewInverse.Row2).Length();

                    // set the scale of the object
                    worldMatrix.Row1 *= ((Vector3)transfoComp.WorldMatrix.Row1).Length();
                    worldMatrix.Row2 *= ((Vector3)transfoComp.WorldMatrix.Row2).Length();
                    
                    // set the position
                    worldMatrix.TranslationVector = transfoComp.WorldMatrix.TranslationVector;
                }

                // calculate normalized position of the center of the sprite (takes into account the possible rotation of the image)
                var normalizedCenter = new Vector2(sprite.Center.X / sourceRegion.Width - 0.5f, 0.5f - sprite.Center.Y / sourceRegion.Height);
                if (sprite.Orientation == ImageOrientation.Rotated90)
                {
                    var oldCenterX = normalizedCenter.X;
                    normalizedCenter.X = -normalizedCenter.Y;
                    normalizedCenter.Y = oldCenterX;
                }
                // apply the offset due to the center of the sprite
                var centerOffset = Vector2.Modulate(normalizedCenter, sprite.SizeInternal);
                worldMatrix.M41 -= centerOffset.X * worldMatrix.M11 + centerOffset.Y * worldMatrix.M21;
                worldMatrix.M42 -= centerOffset.X * worldMatrix.M12 + centerOffset.Y * worldMatrix.M22;
                worldMatrix.M43 -= centerOffset.X * worldMatrix.M13 + centerOffset.Y * worldMatrix.M23; 

                // draw the sprite
                sprite3DBatch.Draw(texture, ref worldMatrix, ref sourceRegion, ref sprite.SizeInternal, ref color, sprite.Orientation, SwizzleMode.None, renderItem.Depth);
            }

            sprite3DBatch.End();
        }

        protected override void DrawCore(RenderContext context, RenderItemCollection renderItems, int fromIndex, int toIndex)
        {
            var viewParameters = context.Parameters;

            var device = context.GraphicsDevice;
            var viewProjection = viewParameters.Get(TransformationKeys.ViewProjection);

            BlendState previousBlendState = null;
            DepthStencilState previousDepthStencilState = null;
            Effect previousEffect = null;

            var isPicking = context.IsPicking();

            bool hasBegin = false;
            for (var i = fromIndex; i <= toIndex; i++)
            {
                var renderItem = renderItems[i];
                var spriteState = (SpriteStudioProcessor.Data)renderItem.DrawContext;
                var transfoComp = spriteState.TransformComponent;
                var depthStencilState = device.DepthStencilStates.None;

                foreach (var node in spriteState.SpriteStudioComponent.SortedNodes)
                {
                    if (node.Sprite?.Texture == null || node.Sprite.Region.Width <= 0 || node.Sprite.Region.Height <= 0f || node.Hide != 0) continue;

                    // Update the sprite batch

                    BlendState spriteBlending;
                    switch (node.BaseNode.AlphaBlending)
                    {
                        case SpriteStudioBlending.Mix:
                            spriteBlending = device.BlendStates.AlphaBlend;
                            break;
                        case SpriteStudioBlending.Multiplication:
                            spriteBlending = MultBlendState;
                            break;
                        case SpriteStudioBlending.Addition:
                            spriteBlending = device.BlendStates.Additive;
                            break;
                        case SpriteStudioBlending.Subtraction:
                            spriteBlending = SubBlendState;
                            break;
                        default:
                            throw new ArgumentOutOfRangeException();
                    }

                    var blendState = isPicking ? device.BlendStates.Opaque : renderItems.HasTransparency ? spriteBlending : device.BlendStates.Opaque;
                    var currentEffect = isPicking ? GetOrCreatePickingSpriteEffect() : spriteState.SpriteStudioComponent.Tags.Get(IsEntitySelected) ? GetOrCreateSelectedSpriteEffect() : null;
                    // TODO remove this code when material are available
                    if (previousEffect != currentEffect || blendState != previousBlendState || depthStencilState != previousDepthStencilState)
                    {
                        if (hasBegin)
                        {
                            sprite3DBatch.End();
                        }
                        sprite3DBatch.Begin(viewProjection, SpriteSortMode.Deferred, blendState, null, depthStencilState, device.RasterizerStates.CullNone, currentEffect);
                        hasBegin = true;
                    }

                    previousEffect = currentEffect;
                    previousBlendState = blendState;
                    previousDepthStencilState = depthStencilState;

                    var sourceRegion = node.Sprite.Region;
                    var texture = node.Sprite.Texture;

                    // skip the sprite if no texture is set.
                    if (texture == null)
                        continue;

                    var color4 = Color4.White;
                    if (isPicking)
                    {
                        // TODO move this code corresponding to picking out of the runtime code.
                        color4 = new Color4(spriteState.SpriteStudioComponent.Id.ToRuntimeId());
                    }
                    else
                    {
                        if (node.BlendFactor > 0.0f)
                        {
                            switch (node.BlendType) //todo this should be done in a shader
                            {
                                case SpriteStudioBlending.Mix:
                                    color4 = Color4.Lerp(color4, node.BlendColor, node.BlendFactor) * node.FinalTransparency;
                                    break;
                                case SpriteStudioBlending.Multiplication:
                                    color4 = Color4.Lerp(color4, node.BlendColor, node.BlendFactor) * node.FinalTransparency;
                                    break;
                                case SpriteStudioBlending.Addition:
                                    color4 = Color4.Lerp(color4, node.BlendColor, node.BlendFactor) * node.FinalTransparency;
                                    break;
                                case SpriteStudioBlending.Subtraction:
                                    color4 = Color4.Lerp(color4, node.BlendColor, node.BlendFactor) * node.FinalTransparency;
                                    break;
                                default:
                                    throw new ArgumentOutOfRangeException();
                            }
                        }
                        else
                        {
//.........这里部分代码省略.........