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-rw-r--r--examples/qt3d/tessellation-modes/shaders/phongwireframe.frag108
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diff --git a/examples/qt3d/tessellation-modes/shaders/phongwireframe.frag b/examples/qt3d/tessellation-modes/shaders/phongwireframe.frag
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+++ b/examples/qt3d/tessellation-modes/shaders/phongwireframe.frag
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+#version 400 core
+
+uniform struct LightInfo {
+ vec4 position;
+ vec3 intensity;
+} light;
+
+uniform struct LineInfo {
+ float width;
+ vec4 color;
+} line;
+
+uniform vec3 ka; // Ambient reflectivity
+uniform vec3 kd; // Diffuse reflectivity
+uniform vec3 ks; // Specular reflectivity
+uniform float shininess; // Specular shininess factor
+
+in WireframeVertex {
+ vec3 position;
+ vec3 normal;
+ noperspective vec4 edgeA;
+ noperspective vec4 edgeB;
+ flat int configuration;
+} fs_in;
+
+out vec4 fragColor;
+
+vec3 adsModel( const in vec3 pos, const in vec3 n )
+{
+ // Calculate the vector from the light to the fragment
+ vec3 s = normalize( vec3( light.position ) - pos );
+
+ // Calculate the vector from the fragment to the eye position (the
+ // origin since this is in "eye" or "camera" space
+ vec3 v = normalize( -pos );
+
+ // Refleft the light beam using the normal at this fragment
+ vec3 r = reflect( -s, n );
+
+ // Calculate the diffus component
+ vec3 diffuse = vec3( max( dot( s, n ), 0.0 ) );
+
+ // Calculate the specular component
+ vec3 specular = vec3( pow( max( dot( r, v ), 0.0 ), shininess ) );
+
+ // Combine the ambient, diffuse and specular contributions
+ return light.intensity * ( ka + kd * diffuse + ks * specular );
+}
+
+vec4 shadeLine( const in vec4 color )
+{
+ // Find the smallest distance between the fragment and a triangle edge
+ float d;
+ if ( fs_in.configuration == 0 )
+ {
+ // Common configuration
+ d = min( fs_in.edgeA.x, fs_in.edgeA.y );
+ d = min( d, fs_in.edgeA.z );
+ }
+ else
+ {
+ // Handle configuration where screen space projection breaks down
+ // Compute and compare the squared distances
+ vec2 AF = gl_FragCoord.xy - fs_in.edgeA.xy;
+ float sqAF = dot( AF, AF );
+ float AFcosA = dot( AF, fs_in.edgeA.zw );
+ d = abs( sqAF - AFcosA * AFcosA );
+
+ vec2 BF = gl_FragCoord.xy - fs_in.edgeB.xy;
+ float sqBF = dot( BF, BF );
+ float BFcosB = dot( BF, fs_in.edgeB.zw );
+ d = min( d, abs( sqBF - BFcosB * BFcosB ) );
+
+ // Only need to care about the 3rd edge for some configurations.
+ if ( fs_in.configuration == 1 || fs_in.configuration == 2 || fs_in.configuration == 4 )
+ {
+ float AFcosA0 = dot( AF, normalize( fs_in.edgeB.xy - fs_in.edgeA.xy ) );
+ d = min( d, abs( sqAF - AFcosA0 * AFcosA0 ) );
+ }
+
+ d = sqrt( d );
+ }
+
+ // Blend between line color and phong color
+ float mixVal;
+ if ( d < line.width - 1.0 )
+ {
+ mixVal = 1.0;
+ }
+ else if ( d > line.width + 1.0 )
+ {
+ mixVal = 0.0;
+ }
+ else
+ {
+ float x = d - ( line.width - 1.0 );
+ mixVal = exp2( -2.0 * ( x * x ) );
+ }
+
+ return mix( color, line.color, mixVal );
+}
+
+void main()
+{
+ // Calculate the color from the phong model
+ vec4 color = vec4( adsModel( fs_in.position, normalize( fs_in.normal ) ), 1.0 );
+ fragColor = shadeLine( color );
+}