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Diffstat (limited to 'common/gal/opengl/shader.vert')
-rw-r--r-- | common/gal/opengl/shader.vert | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/common/gal/opengl/shader.vert b/common/gal/opengl/shader.vert new file mode 100644 index 0000000..24521a4 --- /dev/null +++ b/common/gal/opengl/shader.vert @@ -0,0 +1,95 @@ +/* + * This program source code file is part of KICAD, a free EDA CAD application. + * + * Copyright (C) 2013 CERN + * @author Maciej Suminski <maciej.suminski@cern.ch> + * + * Vertex 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 + +// Shader types +const float SHADER_LINE = 1.0; +const float SHADER_FILLED_CIRCLE = 2.0; +const float SHADER_STROKED_CIRCLE = 3.0; + +// Minimum line width +const float MIN_WIDTH = 1.0; + +attribute vec4 attrShaderParams; +varying vec4 shaderParams; +varying vec2 circleCoords; + +void main() +{ + // Pass attributes to the fragment shader + shaderParams = attrShaderParams; + + if( shaderParams[0] == SHADER_LINE ) + { + float lineWidth = shaderParams[3]; + float worldScale = gl_ModelViewMatrix[0][0]; + + // Make lines appear to be at least 1 pixel wide + if( worldScale * lineWidth < MIN_WIDTH ) + gl_Position = gl_ModelViewProjectionMatrix * + ( gl_Vertex + vec4( shaderParams.yz * MIN_WIDTH / ( worldScale * lineWidth ), 0.0, 0.0 ) ); + else + gl_Position = gl_ModelViewProjectionMatrix * + ( gl_Vertex + vec4( shaderParams.yz, 0.0, 0.0 ) ); + } + else if( ( shaderParams[0] == SHADER_STROKED_CIRCLE ) || + ( shaderParams[0] == SHADER_FILLED_CIRCLE ) ) + { + // Compute relative circle coordinates basing on indices + // Circle + if( shaderParams[1] == 1.0 ) + circleCoords = vec2( -sqrt( 3.0 ), -1.0 ); + else if( shaderParams[1] == 2.0 ) + circleCoords = vec2( sqrt( 3.0 ), -1.0 ); + else if( shaderParams[1] == 3.0 ) + circleCoords = vec2( 0.0, 2.0 ); + + // Semicircle + else if( shaderParams[1] == 4.0 ) + circleCoords = vec2( -3.0 / sqrt( 3.0 ), 0.0 ); + else if( shaderParams[1] == 5.0 ) + circleCoords = vec2( 3.0 / sqrt( 3.0 ), 0.0 ); + else if( shaderParams[1] == 6.0 ) + circleCoords = vec2( 0.0, 2.0 ); + + // Make the line appear to be at least 1 pixel wide + float lineWidth = shaderParams[3]; + float worldScale = gl_ModelViewMatrix[0][0]; + + if( worldScale * lineWidth < MIN_WIDTH ) + shaderParams[3] = shaderParams[3] / ( worldScale * lineWidth ); + + gl_Position = ftransform(); + } + else + { + // Pass through the coordinates like in the fixed pipeline + gl_Position = ftransform(); + } + + gl_FrontColor = gl_Color; +} |