124 lines
3.7 KiB
GLSL
124 lines
3.7 KiB
GLSL
/*
|
|
* This program source code file is part of KICAD, a free EDA CAD application.
|
|
*
|
|
* Copyright (C) 2012 Torsten Hueter, torstenhtr <at> gmx.de
|
|
* Copyright (C) 2012 Kicad Developers, see change_log.txt for contributors.
|
|
*
|
|
* Geometry shader
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version 2
|
|
* of the License, or (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, you may find one here:
|
|
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
|
|
* or you may search the http://www.gnu.org website for the version 2 license,
|
|
* or you may write to the Free Software Foundation, Inc.,
|
|
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
|
|
*/
|
|
|
|
#version 120
|
|
#extension GL_EXT_geometry_shader4: enable
|
|
#extension GL_EXT_gpu_shader4: enable
|
|
|
|
uniform float viewPortX2;
|
|
uniform float viewPortY2;
|
|
varying float dist;
|
|
|
|
void main()
|
|
{
|
|
// Compute the transformed start and end points
|
|
vec2 startPoint = gl_PositionIn[0].xy;
|
|
vec2 endPoint = gl_PositionIn[1].xy;
|
|
float lineWidth = gl_PositionIn[1].z;
|
|
|
|
// Compute vector start -> end
|
|
vec2 startEndVector = endPoint.xy - startPoint.xy;
|
|
float lineLength = distance( startPoint, endPoint );
|
|
float scale = 0.0;
|
|
|
|
if( lineLength > 0.0 )
|
|
{
|
|
scale = 0.5 * lineWidth / lineLength;
|
|
}
|
|
else
|
|
{
|
|
scale = 0.0;
|
|
}
|
|
|
|
// Compute the edge points of the line
|
|
vec2 perpendicularVector = scale * vec2( -startEndVector.y, startEndVector.x );
|
|
vec2 point1 = startPoint + perpendicularVector;
|
|
vec2 point2 = startPoint - perpendicularVector;
|
|
vec2 point3 = endPoint + perpendicularVector;
|
|
vec2 point4 = endPoint - perpendicularVector;
|
|
|
|
vec4 point1T = gl_ModelViewProjectionMatrix * vec4( point1, gl_PositionIn[0].zw );
|
|
vec4 point2T = gl_ModelViewProjectionMatrix * vec4( point2, gl_PositionIn[0].zw );
|
|
vec4 point3T = gl_ModelViewProjectionMatrix * vec4( point3, gl_PositionIn[0].zw );
|
|
vec4 point4T = gl_ModelViewProjectionMatrix * vec4( point4, gl_PositionIn[0].zw );
|
|
|
|
// Construct the quad for the middle
|
|
gl_FrontColor = gl_FrontColorIn[0];
|
|
dist = 0;
|
|
gl_Position = point1T;
|
|
EmitVertex();
|
|
dist = 0;
|
|
gl_Position = point2T;
|
|
EmitVertex();
|
|
dist = 0;
|
|
gl_Position = point3T;
|
|
EmitVertex();
|
|
dist = 0;
|
|
gl_Position = point4T;
|
|
EmitVertex();
|
|
|
|
EndPrimitive();
|
|
|
|
// Compute the perpendicular vector with 1 pixel width
|
|
vec2 v = point1T.xy - point3T.xy;
|
|
vec4 onePix = 0.5 * vec4( -v.y, v.x, 0, 0 );
|
|
onePix *= 1.0 / sqrt( dot( onePix, onePix ) );
|
|
onePix.x *= 1.0 / viewPortX2;
|
|
onePix.y *= 1.0 / viewPortY2;
|
|
|
|
gl_FrontColor = gl_FrontColorIn[0];
|
|
|
|
dist = 1;
|
|
gl_Position = point1T + onePix;
|
|
EmitVertex();
|
|
dist = 1;
|
|
gl_Position = point3T + onePix;
|
|
EmitVertex();
|
|
dist = 0;
|
|
gl_Position = point1T;
|
|
EmitVertex();
|
|
dist = 0;
|
|
gl_Position = point3T;
|
|
EmitVertex();
|
|
|
|
EndPrimitive();
|
|
|
|
dist = 1;
|
|
gl_Position = point2T - onePix;
|
|
EmitVertex();
|
|
dist = 1;
|
|
gl_Position = point4T - onePix;
|
|
EmitVertex();
|
|
dist = 0;
|
|
gl_Position = point2T;
|
|
EmitVertex();
|
|
dist = 0;
|
|
gl_Position = point4T;
|
|
EmitVertex();
|
|
|
|
EndPrimitive();
|
|
}
|