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// ----------------------------------------------------------------------------
// Copyright (c) 2014, Nicolas P. Rougier. All Rights Reserved.
// Distributed under the (new) BSD License.
// ----------------------------------------------------------------------------
#include "antialias/stroke.glsl"
// Cap types
// ----------------------------
const int CAP_NONE = 0;
const int CAP_ROUND = 1;
const int CAP_TRIANGLE_IN = 2;
const int CAP_TRIANGLE_OUT = 3;
const int CAP_SQUARE = 4;
const int CAP_BUTT = 5;
/* ---------------------------------------------------------
Compute antialiased fragment color for a line cap.
Require the stroke function.
Parameters:
-----------
type : Type of cap
dx,dy : signed distances to cap point (in pixels)
linewidth: Stroke line width (in pixels)
antialias: Stroke antialiased area (in pixels)
stroke: Stroke color
Return:
-------
Fragment color (vec4)
--------------------------------------------------------- */
vec4 cap(int type, float dx, float dy, float linewidth, float antialias, vec4 color)
{
float d = 0.0;
dx = abs(dx);
dy = abs(dy);
float t = linewidth/2.0 - antialias;
// Round
if (type == CAP_ROUND)
d = sqrt(dx*dx+dy*dy);
// Square
else if (type == CAP_SQUARE)
d = max(dx,dy);
// Butt
else if (type == CAP_BUTT)
d = max(dx+t,dy);
// Triangle in
else if (type == CAP_TRIANGLE_IN)
d = (dx+abs(dy));
// Triangle out
else if (type == CAP_TRIANGLE_OUT)
d = max(abs(dy),(t+dx-abs(dy)));
// None
else
discard;
return stroke(d, linewidth, antialias, color);
}
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