resolve pb of clipping with line Shaders

CGoGN/include/Utils/Shaders/shaderBold3DColorLines.frag

@@ -4,14 +4,10 @@ PRECISION;
 
 VARYING_FRAG vec3 fragColor;
 uniform float alpha;
-uniform vec4 planeClip;
-VARYING_FRAG vec3 fragClip;
 
 FRAG_OUT_DEF;
 
 void main()
 {
-	if (dot(planeClip,vec4(fragClip,1.0))>0.0)
-		discard;
 	FRAG_OUT = vec4(fragColor,alpha);
 }

CGoGN/include/Utils/Shaders/shaderBold3DColorLines.geom

 // ShaderBold3DColorLines::geometryShaderText
 
-uniform float lineWidth;
+uniform mat4 ModelViewMatrix;
 uniform mat4 ProjectionMatrix;
+uniform float lineWidth;
+uniform vec4 planeClip;
 
 VARYING_IN vec3 vcolor[];
 VARYING_OUT vec3 fragColor;
 
-VARYING_IN vec3 posClip[];
-VARYING_OUT vec3 fragClip;
-
-
 void main()
 {
-	vec4 Ap = (ProjectionMatrix*POSITION_IN(0));
-	vec4 Bp = (ProjectionMatrix*POSITION_IN(1));
+/*
+	float v0 = dot(planeClip,POSITION_IN(0));
+	float v1 = dot(planeClip,POSITION_IN(1));
+
+	vec4 A = vec4(0.0,0.0,0.0,0.0);
+	vec4 B = vec4(0.0,0.0,0.0,0.0);
+
+	if (v0 <= 0.0) //A not clipped
+	{
+		A =  ModelViewMatrix *POSITION_IN(0);
+		if (v1 <= 0.0)
+			B = ModelViewMatrix *POSITION_IN(1);
+		else
+			B = ModelViewMatrix * vec4(POSITION_IN(0).xyz * v1/(v1-v0) - POSITION_IN(1).xyz * v0/(v1-v0) ,1.0);	
+	}
+	else
+	{
+		if (v1 <= 0.0) //B not clipped
+		{
+			B = ModelViewMatrix *POSITION_IN(1);
+			A = ModelViewMatrix * vec4(POSITION_IN(1).xyz * v0/(v0-v1) - POSITION_IN(0).xyz * v1/(v0-v1) ,1.0);		
+		}
+	}
+*/
+	vec4 A = ModelViewMatrix*POSITION_IN(0);
+	vec4 B = ModelViewMatrix*POSITION_IN(1);
+
+
+	vec4 Ap = ProjectionMatrix*A;
+	vec4 Bp = ProjectionMatrix*B;
 
 	vec3 U3 = normalize((Bp.xyz/Bp.w - Ap.xyz/Ap.w));
 	vec3 U = vec3(lineWidth*U3);
 	vec3 V = vec3(lineWidth*normalize(vec2(U[1],-U[0])), 0.0);
 
-	fragClip = posClip[0];
 	fragColor = vcolor[0];
-	gl_Position = ProjectionMatrix*vec4(POSITION_IN(0).xyz-U, 1.0);
+	gl_Position = ProjectionMatrix*vec4(A.xyz-U, 1.0);
 	EmitVertex();
-	gl_Position = ProjectionMatrix*vec4(POSITION_IN(0).xyz+V, 1.0);
+	gl_Position = ProjectionMatrix*vec4(A.xyz+V, 1.0);
 	EmitVertex();
-	gl_Position = ProjectionMatrix*vec4(POSITION_IN(0).xyz-V, 1.0);
+	gl_Position = ProjectionMatrix*vec4(A.xyz-V, 1.0);
 	EmitVertex();
-	fragClip = posClip[1];
 	fragColor = vcolor[1];
-	gl_Position = ProjectionMatrix*vec4(POSITION_IN(1).xyz+V, 1.0);
+	gl_Position = ProjectionMatrix*vec4(B.xyz+V, 1.0);
 	EmitVertex();
-	gl_Position = ProjectionMatrix*vec4(POSITION_IN(1).xyz-V, 1.0);
+	gl_Position = ProjectionMatrix*vec4(B.xyz-V, 1.0);
 	EmitVertex();
-	gl_Position = ProjectionMatrix*vec4(POSITION_IN(1).xyz+U, 1.0);
+	gl_Position = ProjectionMatrix*vec4(B.xyz+U, 1.0);
 	EmitVertex();
 	EndPrimitive();
 }

CGoGN/include/Utils/Shaders/shaderBold3DColorLines.vert

@@ -2,14 +2,12 @@
 
 ATTRIBUTE vec3 VertexPosition;
 ATTRIBUTE vec3 VertexColor;
-uniform mat4 ModelViewMatrix;
 VARYING_VERT vec3 vcolor;
-VARYING_VERT vec3 posClip;
+
 
 INVARIANT_POS;
 void main ()
 {
-	posClip = VertexPosition;
 	vcolor = VertexColor;
-	gl_Position = ModelViewMatrix * vec4 (VertexPosition, 1.0);
+	gl_Position = vec4 (VertexPosition, 1.0);
 }

CGoGN/include/Utils/Shaders/shaderBold3DLines.frag

 // ShaderBold3DLines::fragmentShaderText
 
 PRECISION;
+
 uniform vec4 lineColor;
-uniform vec4 planeClip;
-VARYING_FRAG vec3 fragClip;
+
 FRAG_OUT_DEF;
 
 void main()
 {
-	if (dot(planeClip,vec4(fragClip,1.0))>0.0)
-		discard;
 	FRAG_OUT = lineColor;
 }

CGoGN/include/Utils/Shaders/shaderBold3DLines.geom

 // ShaderBold3DLines::geometryShaderText
 
+uniform mat4 ModelViewMatrix;
 uniform mat4 ProjectionMatrix;
 uniform float lineWidth;
-VARYING_IN vec3 posClip[];
-VARYING_OUT vec3 fragClip;
+uniform vec4 planeClip;
 
 void main()
 {
-	vec4 Ap = (ProjectionMatrix*POSITION_IN(0));
-	vec4 Bp = (ProjectionMatrix*POSITION_IN(1));
+	float v0 = dot(planeClip,POSITION_IN(0));
+	float v1 = dot(planeClip,POSITION_IN(1));
+
+	vec4 A = vec4(0.0,0.0,0.0,0.0);
+	vec4 B = vec4(0.0,0.0,0.0,0.0);
+
+	if (v0 <= 0.0) //A not clipped
+	{
+		A =  ModelViewMatrix *POSITION_IN(0);
+		if (v1 <= 0.0)
+			B = ModelViewMatrix *POSITION_IN(1);
+		else
+			B = ModelViewMatrix * vec4(POSITION_IN(0).xyz * v1/(v1-v0) - POSITION_IN(1).xyz * v0/(v1-v0) ,1.0);	
+	}
+	else
+	{
+		if (v1 <= 0.0) //B not clipped
+		{
+			B = ModelViewMatrix *POSITION_IN(1);
+			A = ModelViewMatrix * vec4(POSITION_IN(1).xyz * v0/(v0-v1) - POSITION_IN(0).xyz * v1/(v0-v1) ,1.0);		
+		}
+	}
+
+
+	vec4 Ap = (ProjectionMatrix*A);
+	vec4 Bp = (ProjectionMatrix*B);
 
 	vec3 U3 = normalize((Bp.xyz/Bp.w - Ap.xyz/Ap.w));
 	vec3 U = vec3(lineWidth*U3);
 	vec3 V = vec3(lineWidth*normalize(vec2(U[1],-U[0])), 0.0);
 
-	fragClip = posClip[0];
-	gl_Position = ProjectionMatrix*vec4(POSITION_IN(0).xyz-U, 1.0);
+	gl_Position = ProjectionMatrix*vec4(A.xyz-U, 1.0);
 	EmitVertex();
-	gl_Position = ProjectionMatrix*vec4(POSITION_IN(0).xyz+V, 1.0);
+	gl_Position = ProjectionMatrix*vec4(A.xyz+V, 1.0);
 	EmitVertex();
-	gl_Position = ProjectionMatrix*vec4(POSITION_IN(0).xyz-V, 1.0);
+	gl_Position = ProjectionMatrix*vec4(A.xyz-V, 1.0);
 	EmitVertex();
-	fragClip = posClip[1];
-	gl_Position = ProjectionMatrix*vec4(POSITION_IN(1).xyz+V, 1.0);
+	gl_Position = ProjectionMatrix*vec4(B.xyz+V, 1.0);
 	EmitVertex();
-	gl_Position = ProjectionMatrix*vec4(POSITION_IN(1).xyz-V, 1.0);
+	gl_Position = ProjectionMatrix*vec4(B.xyz-V, 1.0);
 	EmitVertex();
-	gl_Position = ProjectionMatrix*vec4(POSITION_IN(1).xyz+U, 1.0);
+	gl_Position = ProjectionMatrix*vec4(B.xyz+U, 1.0);
 	EmitVertex();
 	EndPrimitive();
 }

CGoGN/include/Utils/Shaders/shaderBold3DLines.vert

 // ShaderBold3DLines::vertexShaderText
 
 ATTRIBUTE vec3 VertexPosition;
-uniform mat4 ModelViewMatrix;
-VARYING_VERT vec3 posClip;
 
 INVARIANT_POS;
 void main ()
 {
 	posClip = VertexPosition;
-	gl_Position = ModelViewMatrix * vec4 (VertexPosition, 1.0);
+	gl_Position = vec4 (VertexPosition, 1.0);
 }

CGoGN/include/Utils/Shaders/shaderBoldColorLines.frag

@@ -4,14 +4,10 @@ PRECISION;
 
 VARYING_FRAG vec3 fragColor;
 uniform float alpha;
-uniform vec4 planeClip;
-VARYING_FRAG vec3 fragClip;
 
 FRAG_OUT_DEF;
 
 void main()
 {
-	if (dot(planeClip,vec4(fragClip,1.0))>0.0)
-		discard;
 	FRAG_OUT = vec4(fragColor,alpha);
 }

CGoGN/include/Utils/Shaders/shaderBoldColorLines.geom

 // ShaderBoldColorLines::geometryShaderText
 
-uniform vec2 lineWidths;
+uniform mat4 ModelViewMatrix;
 uniform mat4 ProjectionMatrix;
+uniform vec2 lineWidths;
+uniform vec4 planeClip;
 
 VARYING_IN vec3 vcolor[];
 VARYING_OUT vec3 fragColor;
 
-VARYING_IN vec3 posClip[];
-VARYING_OUT vec3 fragClip;
-
 void main()
 {
-	vec4 A = POSITION_IN(0);
-	vec4 B = POSITION_IN(1);
-	
+	float v0 = dot(planeClip,POSITION_IN(0));
+	float v1 = dot(planeClip,POSITION_IN(1));
+
+	vec4 A = vec4(0.0,0.0,0.0,0.0);
+	vec4 B = vec4(0.0,0.0,0.0,0.0);
+
+	if (v0 <= 0.0) //A not clipped
+	{
+		A =  ModelViewMatrix *POSITION_IN(0);
+		if (v1 <= 0.0)
+			B = ModelViewMatrix *POSITION_IN(1);
+		else
+			B = ModelViewMatrix * vec4(POSITION_IN(0).xyz * v1/(v1-v0) - POSITION_IN(1).xyz * v0/(v1-v0) ,1.0);	
+	}
+	else
+	{
+		if (v1 <= 0.0) //B not clipped
+		{
+			B = ModelViewMatrix *POSITION_IN(1);
+			A = ModelViewMatrix * vec4(POSITION_IN(1).xyz * v0/(v0-v1) - POSITION_IN(0).xyz * v1/(v0-v1) ,1.0);		
+		}
+	}
+
 	float nearZ = 1.0;
 	if (ProjectionMatrix[2][2] !=  1.0)
 		nearZ = - ProjectionMatrix[3][2] / (ProjectionMatrix[2][2] - 1.0); 
 
-
 	if ((A.z < nearZ) || (B.z < nearZ))
 	{
 		if (A.z >= nearZ)
@@ -28,16 +46,15 @@ void main()
 
 		A = ProjectionMatrix*A;
 		B = ProjectionMatrix*B;
-		
+	
 		A = A/A.w;
 		B = B/B.w;
-		
+	
 		vec2 U2 = normalize(vec2(lineWidths[1],lineWidths[0])*(B.xy - A.xy));
 		vec2 LWCorr =lineWidths * max(abs(U2.x),abs(U2.y));
 		vec3 U = vec3(LWCorr*U2,0.0);
 		vec3 V = vec3(LWCorr*vec2(U2[1], -U2[0]), 0.0);
 
-		fragClip = posClip[0];
 		fragColor = vcolor[0];
 		gl_Position = vec4(A.xyz-U, 1.0);
 		EmitVertex();
@@ -46,7 +63,6 @@ void main()
 		gl_Position = vec4(A.xyz-V, 1.0);
 		EmitVertex();
 
-		fragClip = posClip[1];
 		fragColor = vcolor[1];
 		gl_Position = vec4(B.xyz+V, 1.0);
 		EmitVertex();
@@ -54,7 +70,7 @@ void main()
 		EmitVertex();
 		gl_Position = vec4(B.xyz+U, 1.0);
 		EmitVertex();
-		
+	
 		EndPrimitive();
 	}
 }

CGoGN/include/Utils/Shaders/shaderBoldColorLines.vert

@@ -2,14 +2,11 @@
 
 ATTRIBUTE vec3 VertexPosition;
 ATTRIBUTE vec3 VertexColor;
-uniform mat4 ModelViewMatrix;
 VARYING_VERT vec3 vcolor;
-VARYING_VERT vec3 posClip;
 
 INVARIANT_POS;
 void main ()
 {
-	posClip = VertexPosition;
 	vcolor = VertexColor;
-	gl_Position = ModelViewMatrix * vec4 (VertexPosition, 1.0);
+	gl_Position = vec4(VertexPosition, 1.0);
 }

CGoGN/include/Utils/Shaders/shaderBoldLines.frag

@@ -2,13 +2,9 @@
 
 PRECISION;
 uniform vec4 lineColor;
-uniform vec4 planeClip;
-VARYING_FRAG vec3 fragClip;
 FRAG_OUT_DEF;
 
 void main()
 {
-	if (dot(planeClip,vec4(fragClip,1.0))>0.0)
-		discard;
 	FRAG_OUT = lineColor;
 }

CGoGN/include/Utils/Shaders/shaderBoldLines.geom

 // ShaderBoldLines::geometryShaderText
 
+uniform mat4 ModelViewMatrix;
 uniform mat4 ProjectionMatrix;
 uniform vec2 lineWidths;
-VARYING_IN vec3 posClip[];
-VARYING_OUT vec3 fragClip;
+uniform vec4 planeClip;
 
 void main()
 {
-	vec4 A = POSITION_IN(0);
-	vec4 B = POSITION_IN(1);
+	float v0 = dot(planeClip,POSITION_IN(0));
+	float v1 = dot(planeClip,POSITION_IN(1));
+
+	vec4 A = vec4(0.0,0.0,0.0,0.0);
+	vec4 B = vec4(0.0,0.0,0.0,0.0);
+
+	if (v0 <= 0.0) //A not clipped
+	{
+		A =  ModelViewMatrix *POSITION_IN(0);
+		if (v1 <= 0.0)
+			B = ModelViewMatrix *POSITION_IN(1);
+		else
+			B = ModelViewMatrix * vec4(POSITION_IN(0).xyz * v1/(v1-v0) - POSITION_IN(1).xyz * v0/(v1-v0) ,1.0);	
+	}
+	else
+	{
+		if (v1 <= 0.0) //B not clipped
+		{
+			B = ModelViewMatrix *POSITION_IN(1);
+			A = ModelViewMatrix * vec4(POSITION_IN(1).xyz * v0/(v0-v1) - POSITION_IN(0).xyz * v1/(v0-v1) ,1.0);		
+		}
+	}
 
 	float nearZ = 1.0;
 	if (ProjectionMatrix[2][2] !=  1.0)
@@ -31,7 +51,6 @@ void main()
 		vec3 U = vec3(LWCorr*U2,0.0);
 		vec3 V = vec3(LWCorr*vec2(U2[1], -U2[0]), 0.0);
 
-		fragClip = posClip[0];
 		gl_Position = vec4(A.xyz-U, 1.0);
 		EmitVertex();
 		gl_Position = vec4(A.xyz+V, 1.0);
@@ -39,7 +58,6 @@ void main()
 		gl_Position = vec4(A.xyz-V, 1.0);
 		EmitVertex();
 
-		fragClip = posClip[1];
 		gl_Position = vec4(B.xyz+V, 1.0);
 		EmitVertex();
 		gl_Position = vec4(B.xyz-V, 1.0);

CGoGN/include/Utils/Shaders/shaderBoldLines.vert

 // ShaderBoldLines::vertexShaderText
 
 ATTRIBUTE vec3 VertexPosition;
-uniform mat4 ModelViewMatrix;
-VARYING_VERT vec3 posClip;
 
 INVARIANT_POS;
 void main ()
 {
-	posClip = VertexPosition;
-	gl_Position = ModelViewMatrix * vec4 (VertexPosition, 1.0);
+	gl_Position = vec4 (VertexPosition, 1.0);
 }

CGoGN/include/Utils/Shaders/shaderColorDarts.frag

@@ -4,14 +4,10 @@ PRECISION;
 
 VARYING_FRAG vec3 fragColor;
 uniform float alpha;
-uniform vec4 planeClip;
-VARYING_FRAG vec3 fragClip;
 
 FRAG_OUT_DEF;
 
 void main()
 {
-	if (dot(planeClip,vec4(fragClip,1.0))>0.0)
-		discard;
 	FRAG_OUT = vec4(fragColor,alpha);
 }

CGoGN/include/Utils/Shaders/shaderColorDarts.geom

 // ShaderColorDarts::geometryShaderText
 
+uniform mat4 ModelViewMatrix;
 uniform mat4 ProjectionMatrix;
 uniform vec2 lineWidths;
+uniform vec4 planeClip;
 
 VARYING_IN vec3 vcolor[];
 VARYING_OUT vec3 fragColor;
 
-VARYING_IN vec3 posClip[];
-VARYING_OUT vec3 fragClip;
-
-
 void main()
 {
-	vec4 A = POSITION_IN(0);
-	vec4 B = POSITION_IN(1);
+	float v0 = dot(planeClip,POSITION_IN(0));
+	float v1 = dot(planeClip,POSITION_IN(1));
+	float scalePoint = 3.0;
+
+	vec4 A = vec4(0.0,0.0,0.0,0.0);
+	vec4 B = vec4(0.0,0.0,0.0,0.0);
+
+	if (v0 <= 0.0) //A not clipped
+	{
+		A =  ModelViewMatrix *POSITION_IN(0);
+		if (v1 <= 0.0)
+			B = ModelViewMatrix *POSITION_IN(1);
+		else
+			B = ModelViewMatrix * vec4(POSITION_IN(0).xyz * v1/(v1-v0) - POSITION_IN(1).xyz * v0/(v1-v0) ,1.0);	
+	}
+	else
+	{
+		if (v1 <= 0.0) //B not clipped
+		{
+			B = ModelViewMatrix *POSITION_IN(1);
+			A = ModelViewMatrix * vec4(POSITION_IN(1).xyz * v0/(v0-v1) - POSITION_IN(0).xyz * v1/(v0-v1) ,1.0);		
+			scalePoint = 1.0;
+			}
+	}
 	
 	float nearZ = 1.0;
 	if (ProjectionMatrix[2][2] !=  1.0)
@@ -33,29 +53,27 @@ void main()
 		B = B/B.w;
 	
 		vec2 U2 = normalize(vec2(lineWidths[1],lineWidths[0])*(B.xy - A.xy));
-		vec2 LWCorr =lineWidths * max(abs(U2.x),abs(U2.y));
-		vec3 U = vec3(LWCorr*U2,0.0) * 3.0;
-		vec3 V = vec3(LWCorr*vec2(U2[1], -U2[0]), 0.0)*3.0;
+		vec3 U = vec3(lineWidths*U2,0.0)*scalePoint;
+		vec3 V = vec3(lineWidths*vec2(U2[1], -U2[0]), 0.0) * scalePoint;	
 		
-		fragClip = posClip[0];
 		fragColor = vcolor[0];
 		gl_Position = vec4(A.xyz-U+V, 1.0);
 		EmitVertex();
 		gl_Position = vec4(A.xyz-U-V, 1.0);
 		EmitVertex();
+		
 		gl_Position = vec4(A.xyz+U+V, 1.0);
 		EmitVertex();
 		gl_Position = vec4(A.xyz+U-V, 1.0);
 		EmitVertex();
 		
-		V /= 3.0;
+		V /= scalePoint;
 		
 		gl_Position = vec4(A.xyz+V, 1.0);
 		EmitVertex();
 		gl_Position = vec4(A.xyz-V, 1.0);
 		EmitVertex();
 		
-		fragClip = posClip[1];
 		fragColor = vcolor[1];
 		gl_Position = vec4(B.xyz+V, 1.0);
 		EmitVertex();

CGoGN/include/Utils/Shaders/shaderColorDarts.vert

@@ -2,14 +2,11 @@
 
 ATTRIBUTE vec3 VertexPosition;
 ATTRIBUTE vec3 VertexColor;
-uniform mat4 ModelViewMatrix;
 VARYING_VERT vec3 vcolor;
-VARYING_VERT vec3 posClip;
 
 INVARIANT_POS;
 void main ()
 {
-	posClip = VertexPosition;
 	vcolor = VertexColor;
-	gl_Position = ModelViewMatrix * vec4 (VertexPosition, 1.0);
+	gl_Position = vec4 (VertexPosition, 1.0);
 }

CGoGN/include/Utils/Shaders/shaderDarts.frag

@@ -2,14 +2,10 @@
 
 PRECISION;
 uniform vec4 lineColor;
-uniform vec4 planeClip;
-VARYING_FRAG vec3 fragClip;
 
 FRAG_OUT_DEF;
 
 void main()
 {
-	if (dot(planeClip,vec4(fragClip,1.0))>0.0)
-		discard;
 	FRAG_OUT = lineColor;
 }

CGoGN/include/Utils/Shaders/shaderDarts.geom

 // ShaderDarts::geometryShaderText
 
+uniform mat4 ModelViewMatrix;
 uniform mat4 ProjectionMatrix;
 uniform vec2 lineWidths;
-VARYING_IN vec3 posClip[];
-VARYING_OUT vec3 fragClip;
-
+uniform vec4 planeClip;
 
 void main()
 {
-	vec4 A = POSITION_IN(0);
-	vec4 B = POSITION_IN(1);
+	float v0 = dot(planeClip,POSITION_IN(0));
+	float v1 = dot(planeClip,POSITION_IN(1));
+	float scalePoint = 3.0;
+
+	vec4 A = vec4(0.0,0.0,0.0,0.0);
+	vec4 B = vec4(0.0,0.0,0.0,0.0);
+
+	if (v0 <= 0.0) //A not clipped
+	{
+		A =  ModelViewMatrix *POSITION_IN(0);
+		if (v1 <= 0.0)
+			B = ModelViewMatrix *POSITION_IN(1);
+		else
+			B = ModelViewMatrix * vec4(POSITION_IN(0).xyz * v1/(v1-v0) - POSITION_IN(1).xyz * v0/(v1-v0) ,1.0);	
+	}
+	else
+	{
+		if (v1 <= 0.0) //B not clipped
+		{
+			B = ModelViewMatrix *POSITION_IN(1);
+			A = ModelViewMatrix * vec4(POSITION_IN(1).xyz * v0/(v0-v1) - POSITION_IN(0).xyz * v1/(v0-v1) ,1.0);		
+			scalePoint = 1.0;
+		}
+	}
 	
 	float nearZ = 1.0;
 	if (ProjectionMatrix[2][2] !=  1.0)
@@ -28,12 +49,8 @@ void main()
 		B = B/B.w;
 		
 		vec2 U2 = normalize(vec2(lineWidths[1],lineWidths[0])*(B.xy - A.xy));
-		vec2 LWCorr =lineWidths * max(abs(U2.x),abs(U2.y));
-		vec3 U = vec3(LWCorr*U2,0.0)*3.0;
-		vec3 V = vec3(LWCorr*vec2(U2[1], -U2[0]), 0.0)*3.0;
-
-		
-		fragClip = posClip[0];
+		vec3 U = vec3(lineWidths*U2,0.0)*scalePoint;
+		vec3 V = vec3(lineWidths*vec2(U2[1], -U2[0]), 0.0) * scalePoint;
 		
 		gl_Position = vec4(A.xyz-U+V, 1.0);
 		EmitVertex();
@@ -44,14 +61,13 @@ void main()
 		gl_Position = vec4(A.xyz+U-V, 1.0);
 		EmitVertex();
 		
-		V /= 3.0;
+		V /= scalePoint;
 		
 		gl_Position = vec4(A.xyz+V, 1.0);
 		EmitVertex();
 		gl_Position = vec4(A.xyz-V, 1.0);
 		EmitVertex();