支持线条方角，调整BVH叶子结点编码方式，级联阴影平滑过渡，添加滑动条便于调整光源

ArchitectureColoredPainting/Light.cpp

@@ -14,7 +14,7 @@ Light::Light(Camera* camera)
 			+ (1 - lambda) * (camera->NearPlane + i / levelCount * (camera->FarPlane - camera->NearPlane)));
 		//qDebug() << shadowCascadeLevels[i-1];
 	}
-
+	shadowCascadeLevels.push_back(camera->FarPlane);
 }
 
 
@@ -127,19 +127,19 @@ std::vector<QMatrix4x4> Light::getLightSpaceMatrices()
 {
 	std::vector<QMatrix4x4> ret;
 	frustumSizes.clear();
-	for (size_t i = 0; i < shadowCascadeLevels.size() + 1; ++i)
+	for (size_t i = 0; i < shadowCascadeLevels.size(); ++i)
 	{
 		if (i == 0)
 		{
 			ret.push_back(getLightSpaceMatrix(camera->NearPlane, shadowCascadeLevels[i]));
 		}
-		else if (i < shadowCascadeLevels.size())
+		else if (i == 1)
 		{
-			ret.push_back(getLightSpaceMatrix(shadowCascadeLevels[i - 1], shadowCascadeLevels[i]));
+			ret.push_back(getLightSpaceMatrix((1 - blendRatio) * shadowCascadeLevels[i - 1] + blendRatio * camera->NearPlane, shadowCascadeLevels[i]));
 		}
 		else
 		{
-			ret.push_back(getLightSpaceMatrix(shadowCascadeLevels[i - 1], camera->FarPlane));
+			ret.push_back(getLightSpaceMatrix((1 - blendRatio) * shadowCascadeLevels[i - 1] + blendRatio * shadowCascadeLevels[i - 2], shadowCascadeLevels[i]));
 		}
 	}
 	return ret;

ArchitectureColoredPainting/Light.h

@@ -14,6 +14,7 @@ class Light
 public:
     QVector3D lightDirection = QVector3D(0.2, 4, 1).normalized();
     std::vector<float> shadowCascadeLevels;
+    float blendRatio = 0.3;
     std::vector<float> frustumSizes;
     Model* model;
 	Light(Camera* camera);

ArchitectureColoredPainting/MainWindow.cpp

@@ -1,9 +1,15 @@
 #include "MainWindow.h"
+#include "RendererWidget.h"
+#include "qslider.h"
 
 MainWindow::MainWindow(QWidget *parent)
     : QMainWindow(parent)
 {
     ui.setupUi(this);
+    QObject::connect(ui.horizontalSlider, &QSlider::valueChanged,
+        ui.openGLWidget, &RendererWidget::setMainLightPitch);
+    QObject::connect(ui.horizontalSlider_2, &QSlider::valueChanged,
+        ui.openGLWidget, &RendererWidget::setMainLightYaw);
 }
 
 MainWindow::~MainWindow()

ArchitectureColoredPainting/MainWindow.ui

@@ -6,7 +6,7 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>600</width>
+    <width>800</width>
     <height>400</height>
    </rect>
   </property>
@@ -14,9 +14,71 @@
    <string>MainWindow</string>
   </property>
   <widget class="QWidget" name="centralWidget">
+   <property name="sizePolicy">
+    <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
+     <horstretch>0</horstretch>
+     <verstretch>0</verstretch>
+    </sizepolicy>
+   </property>
    <layout class="QVBoxLayout" name="verticalLayout">
+    <property name="leftMargin">
+     <number>0</number>
+    </property>
+    <property name="topMargin">
+     <number>0</number>
+    </property>
+    <property name="rightMargin">
+     <number>0</number>
+    </property>
+    <property name="bottomMargin">
+     <number>0</number>
+    </property>
     <item>
-     <widget class="RendererWidget" name="openGLWidget"/>
+     <layout class="QHBoxLayout" name="horizontalLayout" stretch="1,0">
+      <property name="sizeConstraint">
+       <enum>QLayout::SetDefaultConstraint</enum>
+      </property>
+      <item>
+       <widget class="RendererWidget" name="openGLWidget">
+        <property name="sizePolicy">
+         <sizepolicy hsizetype="Preferred" vsizetype="Expanding">
+          <horstretch>0</horstretch>
+          <verstretch>0</verstretch>
+         </sizepolicy>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <layout class="QVBoxLayout" name="verticalLayout_3">
+        <item>
+         <widget class="QSlider" name="horizontalSlider">
+          <property name="sizePolicy">
+           <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
+            <horstretch>0</horstretch>
+            <verstretch>0</verstretch>
+           </sizepolicy>
+          </property>
+          <property name="maximum">
+           <number>180</number>
+          </property>
+          <property name="orientation">
+           <enum>Qt::Horizontal</enum>
+          </property>
+         </widget>
+        </item>
+        <item>
+         <widget class="QSlider" name="horizontalSlider_2">
+          <property name="maximum">
+           <number>360</number>
+          </property>
+          <property name="orientation">
+           <enum>Qt::Horizontal</enum>
+          </property>
+         </widget>
+        </item>
+       </layout>
+      </item>
+     </layout>
     </item>
    </layout>
   </widget>

ArchitectureColoredPainting/Model.cpp

@@ -114,6 +114,12 @@ void Model::processNode(aiNode* node, const aiScene* scene, aiMatrix4x4 mat4)
 		processNode(node->mChildren[i], scene, mat4 * node->mChildren[i]->mTransformation);
 	}
 }
+
+GLuint encodeChild(GLuint index)
+{
+	return 0x80000000 + index;
+}
+
 Drawable* Model::processMesh(aiMesh* mesh, const aiScene* scene, aiMatrix4x4 model)
 {
 	aiMaterial* material = scene->mMaterials[mesh->mMaterialIndex];
@@ -188,12 +194,12 @@ Drawable* Model::processMesh(aiMesh* mesh, const aiScene* scene, aiMatrix4x4 mod
 			//root
 			1,2,
 			3,4, 5,6,
-			7,0, 7,GLuint(30. / 360 * 65536 + 1 * 65536) /*右儿子用来表示旋转角度和zIndex*/, 8,0, 7,0,
+			encodeChild(0),0, encodeChild(0),GLuint(30. / 360 * 65536 + 1 * 65536) /*右儿子用来表示旋转角度和zIndex*/, 	encodeChild(1),0, 	encodeChild(0),0,
 			//elememt0
 			1,2,
-			3 + 20/*contour索引，由于contour不定长，这里需要给到contour在elementIndex中位置*/,3 + 14/*style索引，在elementData中位置*/, 3+24,3+14,
+			encodeChild(20)/*contour索引，由于contour不定长，这里需要给到contour在elementIndex中位置*/,14/*style索引，在elementData中位置*/, encodeChild(24), 14,
 			//elememt1
-			1 + 0/*line索引，element中第几条*/,1 + 27
+			encodeChild(0)/*line索引，element中第几条*/, 27
 
 		};
 		std::vector<QVector4D> bvhBounds = {
@@ -205,7 +211,7 @@ Drawable* Model::processMesh(aiMesh* mesh, const aiScene* scene, aiMatrix4x4 mod
 			QVector4D(-1,-1,1,1),
 			QVector4D(-1,-1,-0.2,1), QVector4D(-0.2,-1,1,1),
 			//elememt1
-			QVector4D(-1,0,1,1)
+			QVector4D(-1,-1,1,1)
 		};
 		std::vector<GLuint> elementOffset = {
 			//element0
@@ -250,7 +256,7 @@ Drawable* Model::processMesh(aiMesh* mesh, const aiScene* scene, aiMatrix4x4 mod
 
 			//element1
 			//points
-			-1,0.5, 0,1, 1,0.5,
+			0,0.8, 1,0, 0,-0.8,
 			//strokeStyle
 			//stroke
 			1,
@@ -260,8 +266,14 @@ Drawable* Model::processMesh(aiMesh* mesh, const aiScene* scene, aiMatrix4x4 mod
 			0, //Ô²½Ç
 			//strokeFillType
 			0, //µ¥É«
+			//线类型
+			1, //左侧
+			//线外描边宽度
+			0,
+			//线外描边方式
+			0, //单色
 			//strokeFillColorMetallicRoughness
-			0,1,0, 0,0.8
+			1,0,1, 0,0.8
 		};
 
 		//m_mesh->paintingIndex = paintingHelper->addPainting(bounds.size(), std::vector<GLuint>(children.begin()+2, children.end()), bounds,

ArchitectureColoredPainting/RendererWidget.cpp

@@ -7,6 +7,10 @@
 #include <QGuiApplication>
 #include <random>
 
+//QVector3D lightPositions[] = { 2000 * QVector3D(0.2, 4, 1).normalized(), QVector3D(100,100,100) ,QVector3D(-100,100,100) ,QVector3D(100,100,-100) };
+QVector3D lightColors[] = { 20 * QVector3D(0.7529,0.7450,0.6784).normalized(), QVector3D(0,0,0) ,QVector3D(0,0,0) ,QVector3D(0,0,0) };
+static float sunPitch = 90, sunYaw = 80;
+static int sunSpeed = 10;
 
 RendererWidget::RendererWidget(QWidget* parent)
 	: QOpenGLWidget(parent)
@@ -47,6 +51,17 @@ RendererWidget::~RendererWidget()
 	}
 }
 
+void RendererWidget::setMainLightPitch(float pitch)
+{
+	//qDebug() << "pitch" << pitch;
+	sunPitch = pitch;
+}
+
+void RendererWidget::setMainLightYaw(float yaw)
+{
+	//qDebug() << "yaw" << yaw;
+	sunYaw = yaw;
+}
 QOpenGLTexture randomMap(QOpenGLTexture::Target2D);
 void RendererWidget::initializeGL()
 {
@@ -190,6 +205,7 @@ void RendererWidget::initializeGL()
 	paintingHelper = new PaintingHelper(QOpenGLContext::currentContext()->versionFunctions<QOpenGLFunctions_4_5_Compatibility>());
 
 	model = new Model("Models/Sponza/Sponza.gltf", context(), modelProgramPtr, paintingProgramPtr, shadowProgramPtr, paintingHelper);
+	//model = new Model("E:\\3D Objects\\gallery_gltf\\gallery_gltf.gltf", context(), modelProgramPtr, paintingProgramPtr, shadowProgramPtr, paintingHelper);
 	light.model = model;
 	qDebug() << model->AABB;
 
@@ -226,10 +242,7 @@ void RendererWidget::initializeGL()
 
 
 }
-//QVector3D lightPositions[] = { 2000 * QVector3D(0.2, 4, 1).normalized(), QVector3D(100,100,100) ,QVector3D(-100,100,100) ,QVector3D(100,100,-100) };
+
-QVector3D lightColors[] = { 20 * QVector3D(0.7529,0.7450,0.6784).normalized(), QVector3D(0,0,0) ,QVector3D(0,0,0) ,QVector3D(0,0,0) };
-static float sunPitch = 90, sunYaw = 80;
-static int sunSpeed = 10;
 void RendererWidget::paintGL()
 {
 	light.lightDirection.setX(cos(qDegreesToRadians(sunPitch)) * cos(qDegreesToRadians(sunYaw)));
@@ -309,6 +322,7 @@ void RendererWidget::paintGL()
 	shadowMappingProgramPtr->setUniformValueArray("shadowBiases", light.frustumSizes.data(), light.frustumSizes.size(), 1);
 	//qDebug() << light.frustumSizes;
 	shadowMappingProgramPtr->setUniformValue("shadowCascadeCount", (GLint)light.shadowCascadeLevels.size());
+	shadowMappingProgramPtr->setUniformValue("shadowBlendRatio", light.blendRatio);
 	shadowMappingProgramPtr->setUniformValue("camPos", camera.Position);
 	shadowMappingProgramPtr->setUniformValue("mainLightDirection", light.lightDirection);
 	shadowMappingProgramPtr->setUniformValue("mainLightRadiance", lightColors[0]);
@@ -379,8 +393,8 @@ void RendererWidget::paintGL()
 
 void RendererWidget::resizeGL(int width, int height)
 {
-	frameWidth = devicePixelRatioF() * width;
+	frameWidth = ceil( devicePixelRatioF() * width);
-	frameHeight = devicePixelRatioF() * height;
+	frameHeight = ceil(devicePixelRatioF() * height);
 	qDebug() << frameWidth << "x" << frameHeight;
 	camera.Ratio = (float)frameWidth / (float)frameHeight;
 	//qDebug() << devicePixelRatioF() << width << height;
@@ -492,7 +506,7 @@ void RendererWidget::resizeGL(int width, int height)
 		//Depth
 		glBindTexture(GL_TEXTURE_2D_ARRAY, shadowGbuffer);
 		glTexImage3D(
-			GL_TEXTURE_2D_ARRAY, 0, GL_DEPTH_COMPONENT32F, shadowMapResolution, shadowMapResolution, int(light.shadowCascadeLevels.size()) + 1,
+			GL_TEXTURE_2D_ARRAY, 0, GL_DEPTH_COMPONENT32F, shadowMapResolution, shadowMapResolution, int(light.shadowCascadeLevels.size()),
 			0, GL_DEPTH_COMPONENT, GL_FLOAT, nullptr);
 
 		/*glBindTexture(GL_TEXTURE_2D, shadowGbuffer);
@@ -565,12 +579,12 @@ void RendererWidget::timerEvent(QTimerEvent* event)
 	}
 
 
-	sunPitch += sunSpeed * deltaTime;
+	/*sunPitch += sunSpeed * deltaTime;
 	if (sunPitch > 120 || sunPitch < 65)
 	{
 		sunSpeed = -sunSpeed;
 		sunPitch += sunSpeed * deltaTime;
-	}
+	}*/
 
 	repaint();
 }

ArchitectureColoredPainting/RendererWidget.h

@@ -19,6 +19,9 @@ public:
     RendererWidget(QWidget* parent = nullptr);
     ~RendererWidget();
 
+public slots:
+    void setMainLightPitch(float pitch);
+    void setMainLightYaw(float yaw);
 protected:
     void initializeGL() override;
     void paintGL() override;

ArchitectureColoredPainting/Shaders/painting.comp

@@ -486,7 +486,7 @@ int solve_quartic(vec4 coeffs, inout vec4 s){
 
     return num;
 }
-float cubic_bezier_dis(vec2 uv, vec2 p0, vec2 p1, vec2 p2, vec2 p3){
+float cubic_bezier_dis(vec2 uv, vec2 p0, vec2 p1, vec2 p2, vec2 p3, bool roundEnd){
 
 	//switch points when near to end point to minimize numerical error
 	//only needed when control point(s) very far away
@@ -689,18 +689,32 @@ float cubic_bezier_dis(vec2 uv, vec2 p0, vec2 p1, vec2 p2, vec2 p3){
 			
 
             //compute squared distance to nearest point on curve
+			if(roundEnd)
+			{
 				roots[i] = clamp(roots[i],0.,1.);
 				vec2 to_curve = uv - parametric_cub_bezier(roots[i],p0,p1,p2,p3);
 				d0 = min(d0,dot(to_curve,to_curve));
 			}
+			else
+			{
+				if(roots[i]<0.||roots[i]>1.) d0=min(d0,1e38);
+			    else
+				{
+					vec2 to_curve = uv - parametric_cub_bezier(roots[i],p0,p1,p2,p3);
+					d0 = min(d0,dot(to_curve,to_curve));
+				}
+			}
+			
+		}
 	}
 
 	return sqrt(d0);
 }
 
-vec3 drawElement(uint elementIndex, vec2 localUV, inout vec3 debugBVH = vec3(0))
+bool drawElement(uint elementIndex, vec2 localUV, out vec3 color, inout vec3 debugBVH = vec3(0))
 {
-	vec4 elementColor = vec4(0);
+	bool hitElement = false;
+	vec4 elementColor = vec4(-1);
 
 	uint currentOffset[4] = elementOffset[elementIndex];
 	uint elementBvhRoot = currentOffset[0];
@@ -724,11 +738,11 @@ vec3 drawElement(uint elementIndex, vec2 localUV, inout vec3 debugBVH = vec3(0))
 				{
 					debugBVH.g += 0.5;
 
-					uint styleIndex = bvhChildren[elementBvhRoot + elementBvhIndex].y - elementBvhLength;
+					uint styleIndex = bvhChildren[elementBvhRoot + elementBvhIndex].y;
 					// for(int i = 0; i<200;i++)
 					if (elementData[styleIndex] == 0.) //Ãæ
 					{
-						uint contourIndex = leftChild - elementBvhLength; 
+						uint contourIndex = leftChild - 0x80000000; 
 					
 						uint num_its = 0;
 
@@ -760,16 +774,22 @@ vec3 drawElement(uint elementIndex, vec2 localUV, inout vec3 debugBVH = vec3(0))
 								num_its += cubic_bezier_int_test(localUV, p0, p1, p2, p3);
 						}
 
-						if (num_its % 2 == 1)
+						if (num_its % 2 == 1 && elementColor.a<1)
 						{
-							elementColor = vec4(1);
+							hitElement = true;
-							//debugHit = true;
+							elementColor = vec4(1,1,0,0);
+							if(elementData[styleIndex+1]==0)
+							{
+								elementColor = vec4(elementData[styleIndex+2],elementData[styleIndex+3],elementData[styleIndex+4],0);
+							}
+						
+						
 						}
 					}
 					else if (elementData[styleIndex] == 1) //Ïß  
 					{
 						float strokeWidth = elementData[styleIndex+1];
-						uint lineIndex = leftChild - elementBvhLength; 
+						uint lineIndex = leftChild - 0x80000000; 
 						uint p0Index = elementIndexs[linesOffset + 4 * lineIndex];
 						uint p1Index = elementIndexs[linesOffset + 4 * lineIndex + 1];
 						uint p2Index = elementIndexs[linesOffset + 4 * lineIndex + 2];
@@ -784,9 +804,23 @@ vec3 drawElement(uint elementIndex, vec2 localUV, inout vec3 debugBVH = vec3(0))
 						vec2 p3 = vec2(elementData[pointsOffset + 2 * p3Index],
 									   elementData[pointsOffset + 2 * p3Index + 1]);
 
-						if(cubic_bezier_dis(localUV, p0, p1, p2, p3)<=strokeWidth)
+						float lineType = elementData[styleIndex+4];
+						/*if(cubic_bezier_dis(localUV, p0, p1, p2, p3, true)<=0.001)
+						{
+							hitElement = true;
 							elementColor = vec4(1);
 						}	
+						else */if(cubic_bezier_dis(localUV, p0, p1, p2, p3, elementData[styleIndex+2]==0)<=strokeWidth 
+									&&(lineType==2 ||cubic_bezier_int_test(localUV, p0, p1, p2, p3)==lineType))
+						{
+							hitElement = true;
+							elementColor = vec4(1);
+							if(elementData[styleIndex+3]==0)
+							{
+								elementColor = vec4(elementData[styleIndex+7],elementData[styleIndex+8],elementData[styleIndex+9],1);
+							}
+						}	
+					}
 
 					elementBvhIndex = elementBvhLength;
 				}
@@ -807,7 +841,8 @@ vec3 drawElement(uint elementIndex, vec2 localUV, inout vec3 debugBVH = vec3(0))
 			elementBvhIndex = bvhChildren[elementBvhRoot + elementBvhIndex].y;
 		}
 	}
-	return elementColor.xyz;
+	color = elementColor.xyz;
+	return hitElement;
 }
 
 
@@ -824,7 +859,8 @@ void main()
 	vec2 uv = imageLoad(gPaintingTexCoord, pixelLocation).rg;
 
 	vec3 debugBVH = vec3(0);
-	bool debugHit = false;
+	//bool debugHit = false;
+	vec4 color = vec4(-1);
 	stack.top = 0;
 	uint index = 0, visitTime = 0;
 	uint bvhLength = paintingOffsets[paintingIndex-1].y;
@@ -844,15 +880,17 @@ void main()
 				vec2 localUV = uv - (bound.xy + bound.zw) / 2;
 				localUV = rotation * localUV;
 				localUV /= (bound.zw - bound.xy) / 2;
-				if (all(lessThan(vec2(-1), localUV)) && all(lessThan(localUV, vec2(1))))
+				if (all(lessThan(vec2(-1), localUV)) && all(lessThan(localUV, vec2(1))) && zIndex>color.w)
 				{
 					if (zIndex == 1)
 						debugBVH = vec3(1, 0, 1);
-					uint elementIndex = leftChild - bvhLength;
+					//uint elementIndex = leftChild - bvhLength;
 					debugBVH.bg += 0.5 * (localUV + vec2(1));
 
 					debugBVH = vec3(0);
-					debugHit = drawElement(leftChild - bvhLength, localUV, debugBVH) == vec3(1);
+					vec3 elementColor;
+					if(drawElement(leftChild - 0x80000000, localUV, elementColor, debugBVH))
+						color = vec4(elementColor, zIndex);
 				
 				}
 
@@ -875,7 +913,9 @@ void main()
 		}
 	}
 
-	if (debugHit)
+	imageStore(gBaseColor, pixelLocation, vec4(color.rgb,1));
+	return;
+	if (color.a!=-1)
 		imageStore(gBaseColor, pixelLocation, vec4(vec3(1, 1, 0),1));    
 	else
 		imageStore(gBaseColor, pixelLocation, vec4(debugBVH,1));

ArchitectureColoredPainting/Shaders/shadow_mapping.comp

@@ -17,6 +17,7 @@ uniform float farPlane;
 uniform float shadowCascadePlaneDistances[16];
 uniform float shadowBiases[16];
 uniform int shadowCascadeCount;
+uniform float shadowBlendRatio;
 
 uniform vec3 mainLightDirection;
 uniform vec3 mainLightRadiance;
@@ -64,28 +65,9 @@ vec3 fresnelSchlick(float cosTheta, vec3 F0)
 {
 	return F0 + (1.0 - F0) * pow(1.0 - cosTheta, 5.0);
 }
-
+const int pcfRadius = 3;
-float ShadowCalculation(vec3 fragPosWorldSpace, vec3 normal, out int layer)
+float getShadowFromLayer(vec3 fragPosWorldSpace, vec3 normal,int layer)
 {
-    // select cascade layer
-    vec4 fragPosViewSpace = view * vec4(fragPosWorldSpace, 1.0);
-    float depthValue = abs(fragPosViewSpace.z);
-
-    layer = -1;
-    for (int i = 0; i < shadowCascadeCount; ++i)
-    {
-        if (depthValue < shadowCascadePlaneDistances[i])
-        {
-            layer = i;
-            break;
-        }
-    }
-    if (layer == -1)
-    {
-        layer = shadowCascadeCount;
-    }
-
-	int pcfRadius = 3;
     float normalBias = 4. /** (1+pcfRadius)*/ * shadowBiases[layer]*max((1.0 - dot(normal, mainLightDirection)), 0.1)/textureSize(gShadowMap, 0).x;
     vec4 fragPosLightSpace = lightSpaceMatrices[layer] * vec4(fragPosWorldSpace+normal*normalBias, 1.0);
     // perform perspective divide
@@ -114,7 +96,39 @@ float ShadowCalculation(vec3 fragPosWorldSpace, vec3 normal, out int layer)
         }    
     }
     shadow /= (2*pcfRadius+1)*(2*pcfRadius+1);
+	return shadow;
+}
 
+float ShadowCalculation(vec3 fragPosWorldSpace, vec3 normal, out int layer)
+{
+    // select cascade layer
+    vec4 fragPosViewSpace = view * vec4(fragPosWorldSpace, 1.0);
+    float depthValue = abs(fragPosViewSpace.z);
+
+    layer = -1;
+    for (int i = 0; i < shadowCascadeCount; ++i)
+    {
+        if (depthValue < shadowCascadePlaneDistances[i])
+        {
+            layer = i;
+            break;
+        }
+    }
+//    if (layer == -1)
+//    {
+//        layer = shadowCascadeCount;
+//    } 
+	 
+    float shadow = getShadowFromLayer(fragPosWorldSpace,normal,layer);
+        
+
+	float nextLayerBeginDepth = layer==0? (1-shadowBlendRatio)*shadowCascadePlaneDistances[layer]
+										:(1-shadowBlendRatio)*shadowCascadePlaneDistances[layer]+shadowBlendRatio*shadowCascadePlaneDistances[layer-1];
+	if(depthValue > nextLayerBeginDepth)
+	{
+		float shadowNext = getShadowFromLayer(fragPosWorldSpace,normal,layer+1);
+		shadow = mix(shadow,shadowNext, (depthValue-nextLayerBeginDepth)/(shadowCascadePlaneDistances[layer]-nextLayerBeginDepth));
+	}
     return shadow;
 }