diff --git a/core/stickernode.gd b/core/stickernode.gd
index 34ba61f..583915e 100644
--- a/core/stickernode.gd
+++ b/core/stickernode.gd
@@ -38,6 +38,8 @@ var detected_solids:Array
 var detected_zones:Array
 var Grabbed:bool = false
 
+## Emitted when the sticker overlap a blocking body, preventing to be spawned as an asset in the level. Usually received by the cursor to change his sprite
+signal spawn_mode_changed(can_spawn:bool)
 #region Functions
 func _get_configuration_warnings():
 	if (get_parent() == get_tree().get_edited_scene_root()):
@@ -75,17 +77,19 @@ func _ready():
 		area_exited.connect(_on_area_exited)
 		body_entered.connect(_on_body_entered)
 		body_exited.connect(_on_body_exited)
+	
 
 # TODO : Solids and interactive zone detection area should not be the same as the sticker area. 
 # IDEA: Need to export a child Area2D
 func _on_body_entered(body:Node2D):
 	print("body entered",body)
 	detected_solids.append(body)
+	spawn_mode_changed.emit(false)
 func _on_body_exited(body:Node2D):
 	print("body exited",body)
 	detected_solids.erase(body)
-	if(Sticker_mode and Grabbed and detected_solids.size() == 0):
-			print("Can be released in object mode")
+	if(Sticker_mode and Grabbed and detected_solids.size() == 0 ):
+		spawn_mode_changed.emit(true)
 func _on_area_entered(area:Area2D):
 	print("area entered",area)
 	#TODO:Filter by type
diff --git a/shaders/pageflip.gdshader b/shaders/pageflip.gdshader
new file mode 100644
index 0000000..d0bf928
--- /dev/null
+++ b/shaders/pageflip.gdshader
@@ -0,0 +1,142 @@
+shader_type canvas_item;
+uniform vec2 scale = vec2(1,1);
+uniform vec2 flip_pos = vec2(-1.,-1.);
+
+vec2 Line2point(vec2 linePoint,vec2 lineDire,vec2 point) {
+	lineDire = normalize(lineDire);
+	vec2 line2Ori = - linePoint - dot(-linePoint,lineDire)*lineDire;
+	vec2 p2Ori = - point - dot(-point,lineDire)*lineDire;
+	return line2Ori-p2Ori;
+	}
+vec4 ColorWithA(vec4 oldCol,vec4 newCol){
+	vec4 finalCol;
+	if((newCol.a + oldCol.a)>=1.)
+	{
+		finalCol.rgb = newCol.rgb ;
+		finalCol.a =1.0;
+	}
+	else{
+		finalCol.rgb = newCol.a/(newCol.a + oldCol.a)*newCol.rgb + oldCol.a/(newCol.a + oldCol.a)*oldCol.rgb;
+		finalCol.a = oldCol.a +newCol.a;
+		}
+	return 	finalCol;
+	}
+
+void fragment() {
+	vec2 uv = UV;
+//	vec2 mouse_uv = flip_pos ;
+	vec4 finalColor = vec4(0.0); // Initialize with transparent color
+	//拉伸变形校正
+	float scale_min = scale.x/scale.y;
+	vec2 uv_max = vec2(scale_min,1.);
+	float trueScale;
+	if(scale.y<scale.x){
+		scale_min = scale.y/scale.x;
+		uv.y = uv.y * scale_min;
+		uv_max = vec2(1.,scale_min);
+//		mouse_uv = flip_pos * TEXTURE_PIXEL_SIZE /scale.x;
+		trueScale = scale.x;
+		}
+	else{
+		uv.x = uv.x*scale_min;
+//		mouse_uv = flip_pos * TEXTURE_PIXEL_SIZE /scale.y;
+		trueScale = scale.y;
+	}
+
+	COLOR= texture(TEXTURE,uv);
+
+
+	//鼠标响应
+	vec2 pPos = uv / TEXTURE_PIXEL_SIZE * trueScale;
+	if (flip_pos.x>-0.0001)
+	{
+		vec2 left_bottom = vec2(0.,uv_max.y/TEXTURE_PIXEL_SIZE.y * trueScale);
+		vec2 midpoint = (flip_pos - left_bottom)/2. + left_bottom;
+//		vec2 midDirect = vec2(-1.,-1.)/1.414;
+		vec2 midDirect = normalize(vec2(-(flip_pos-left_bottom).y,(flip_pos-left_bottom).x));
+		//bg
+
+		//pageback
+		vec2 sharpPoint = vec2(0.,midpoint.y - midDirect.y/midDirect.x * midpoint.x);
+		vec2 flipEdgeDire = normalize(sharpPoint - flip_pos);
+		//pagebackBottom
+		vec2 sharpPointB = vec2(midpoint.x-midDirect.x/midDirect.y * (midpoint-left_bottom).y,left_bottom.y);
+		vec2 flipEdgeDireB = normalize(sharpPointB - flip_pos);
+
+		//圆柱
+		float cyOriOff = length(flip_pos-left_bottom);
+		if (cyOriOff>100.) cyOriOff = 100.;//圆柱向里面缩进
+		float cyR = cyOriOff*2./PI;
+		float pageHDire = PI/6.;
+		vec2 midlineToP = Line2point(midpoint,midDirect,pPos);
+		vec2 sideEdgeToP = Line2point(flip_pos,flipEdgeDire,pPos);
+		vec2 BottomEdgeToP = Line2point(flip_pos,flipEdgeDireB,pPos);
+
+		vec2 cyOriToP = midlineToP - normalize(flip_pos- left_bottom)*cyOriOff;
+		vec2 cyEdgeToP = midlineToP - normalize(flip_pos- left_bottom)*(cyOriOff-cyR);
+
+		bool atBG = (cyOriToP).x<=-0.01;
+		bool atPageBack = !atBG&&(sideEdgeToP.y>0.)&&(BottomEdgeToP.x<=0.);
+//		bool atCy = (cyOriToP).x<=0.;
+		bool atCy = cyEdgeToP.x >=0. && (cyOriToP).x<=0.;
+		bool atCyPage = false;
+		vec2 uvCy ;
+		vec2 uvCyB ;
+
+
+		float shadow = 1.;
+		if (atCy){
+			vec2 cyOri = pPos-cyOriToP;
+			vec2 trueDis = cyR*  asin(length(cyOriToP)/cyR)*normalize(cyOriToP);
+			vec2 truePos = cyOri+trueDis;
+
+			vec2 sideEdgeToTP = Line2point(flip_pos,flipEdgeDire,truePos);
+			vec2 BottomEdgeToTP = Line2point(flip_pos,flipEdgeDireB,truePos);
+			uvCyB = truePos * TEXTURE_PIXEL_SIZE /trueScale;
+			shadow *= 1.-pow(length(trueDis)/(cyR*PI/2.),3.);
+
+			if ((BottomEdgeToTP.x<0.)&& (sideEdgeToTP.y>0.))
+				{
+					atCyPage = true;
+					uvCy = vec2(length(sideEdgeToTP),left_bottom.y-length(BottomEdgeToTP))*TEXTURE_PIXEL_SIZE /trueScale;
+				}
+
+			if ((uvCyB.x > uv_max.x)||(uvCyB.y > uv_max.y)||(uvCyB.x <= 0.)|| (uvCyB.y <= 0.))
+				atCy =false;
+		}
+
+
+		//色彩
+		COLOR = vec4(0.);
+    // Page
+    if (!atBG && !atCy) {
+        vec4 color = texture(TEXTURE, uv);
+        finalColor = color;
+    }
+
+    // cyBottom
+    if (atCy) {
+        vec4 cyColor = texture(TEXTURE, uvCyB);
+        finalColor = cyColor;
+    }
+
+    if (atCyPage) {
+        vec4 cyPageColor = texture(TEXTURE, uvCy);
+        cyPageColor.xyz *= 0.8;
+        // Blend based on the alpha value of cyPageColor
+        finalColor = mix(finalColor, cyPageColor, cyPageColor.a);
+    } else if (atPageBack) {
+        uv = vec2(length(sideEdgeToP), left_bottom.y - length(BottomEdgeToP)) * TEXTURE_PIXEL_SIZE / trueScale;
+        vec4 pageBackColor = texture(TEXTURE, uv);
+        pageBackColor.xyz *= 0.8;
+        // Blend based on the alpha value of pageBackColor
+        finalColor = mix(finalColor, pageBackColor, pageBackColor.a);
+    }
+
+    COLOR = finalColor;
+}
+
+	// Place fragment code here.
+
+//	FRAGCOORD.xy;
+}
\ No newline at end of file