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+/*
+ * 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;
+}