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// -----------------------------------------------------------------------------
// Copyright (c) 2014, Nicolas P. Rougier. All Rights Reserved.
// Distributed under the (new) BSD License.
// -----------------------------------------------------------------------------
#include "math/constants.glsl"
float marker_cross(vec2 P, float size)
{
float x = M_SQRT2/2.0 * (P.x - P.y);
float y = M_SQRT2/2.0 * (P.x + P.y);
float r1 = max(abs(x - size/3.0), abs(x + size/3.0));
float r2 = max(abs(y - size/3.0), abs(y + size/3.0));
float r3 = max(abs(x), abs(y));
float r = max(min(r1,r2),r3);
r -= size/2.;
return r;
}
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