You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
336 lines
8.5 KiB
336 lines
8.5 KiB
( function () {
|
|
|
|
/**
|
|
* RGB Halftone shader for three.js.
|
|
* NOTE:
|
|
* Shape (1 = Dot, 2 = Ellipse, 3 = Line, 4 = Square)
|
|
* Blending Mode (1 = Linear, 2 = Multiply, 3 = Add, 4 = Lighter, 5 = Darker)
|
|
*/
|
|
|
|
const HalftoneShader = {
|
|
uniforms: {
|
|
'tDiffuse': {
|
|
value: null
|
|
},
|
|
'shape': {
|
|
value: 1
|
|
},
|
|
'radius': {
|
|
value: 4
|
|
},
|
|
'rotateR': {
|
|
value: Math.PI / 12 * 1
|
|
},
|
|
'rotateG': {
|
|
value: Math.PI / 12 * 2
|
|
},
|
|
'rotateB': {
|
|
value: Math.PI / 12 * 3
|
|
},
|
|
'scatter': {
|
|
value: 0
|
|
},
|
|
'width': {
|
|
value: 1
|
|
},
|
|
'height': {
|
|
value: 1
|
|
},
|
|
'blending': {
|
|
value: 1
|
|
},
|
|
'blendingMode': {
|
|
value: 1
|
|
},
|
|
'greyscale': {
|
|
value: false
|
|
},
|
|
'disable': {
|
|
value: false
|
|
}
|
|
},
|
|
vertexShader: /* glsl */`
|
|
|
|
varying vec2 vUV;
|
|
|
|
void main() {
|
|
|
|
vUV = uv;
|
|
gl_Position = projectionMatrix * modelViewMatrix * vec4(position, 1.0);
|
|
|
|
}`,
|
|
fragmentShader: /* glsl */`
|
|
|
|
#define SQRT2_MINUS_ONE 0.41421356
|
|
#define SQRT2_HALF_MINUS_ONE 0.20710678
|
|
#define PI2 6.28318531
|
|
#define SHAPE_DOT 1
|
|
#define SHAPE_ELLIPSE 2
|
|
#define SHAPE_LINE 3
|
|
#define SHAPE_SQUARE 4
|
|
#define BLENDING_LINEAR 1
|
|
#define BLENDING_MULTIPLY 2
|
|
#define BLENDING_ADD 3
|
|
#define BLENDING_LIGHTER 4
|
|
#define BLENDING_DARKER 5
|
|
uniform sampler2D tDiffuse;
|
|
uniform float radius;
|
|
uniform float rotateR;
|
|
uniform float rotateG;
|
|
uniform float rotateB;
|
|
uniform float scatter;
|
|
uniform float width;
|
|
uniform float height;
|
|
uniform int shape;
|
|
uniform bool disable;
|
|
uniform float blending;
|
|
uniform int blendingMode;
|
|
varying vec2 vUV;
|
|
uniform bool greyscale;
|
|
const int samples = 8;
|
|
|
|
float blend( float a, float b, float t ) {
|
|
|
|
// linear blend
|
|
return a * ( 1.0 - t ) + b * t;
|
|
|
|
}
|
|
|
|
float hypot( float x, float y ) {
|
|
|
|
// vector magnitude
|
|
return sqrt( x * x + y * y );
|
|
|
|
}
|
|
|
|
float rand( vec2 seed ){
|
|
|
|
// get pseudo-random number
|
|
return fract( sin( dot( seed.xy, vec2( 12.9898, 78.233 ) ) ) * 43758.5453 );
|
|
|
|
}
|
|
|
|
float distanceToDotRadius( float channel, vec2 coord, vec2 normal, vec2 p, float angle, float rad_max ) {
|
|
|
|
// apply shape-specific transforms
|
|
float dist = hypot( coord.x - p.x, coord.y - p.y );
|
|
float rad = channel;
|
|
|
|
if ( shape == SHAPE_DOT ) {
|
|
|
|
rad = pow( abs( rad ), 1.125 ) * rad_max;
|
|
|
|
} else if ( shape == SHAPE_ELLIPSE ) {
|
|
|
|
rad = pow( abs( rad ), 1.125 ) * rad_max;
|
|
|
|
if ( dist != 0.0 ) {
|
|
float dot_p = abs( ( p.x - coord.x ) / dist * normal.x + ( p.y - coord.y ) / dist * normal.y );
|
|
dist = ( dist * ( 1.0 - SQRT2_HALF_MINUS_ONE ) ) + dot_p * dist * SQRT2_MINUS_ONE;
|
|
}
|
|
|
|
} else if ( shape == SHAPE_LINE ) {
|
|
|
|
rad = pow( abs( rad ), 1.5) * rad_max;
|
|
float dot_p = ( p.x - coord.x ) * normal.x + ( p.y - coord.y ) * normal.y;
|
|
dist = hypot( normal.x * dot_p, normal.y * dot_p );
|
|
|
|
} else if ( shape == SHAPE_SQUARE ) {
|
|
|
|
float theta = atan( p.y - coord.y, p.x - coord.x ) - angle;
|
|
float sin_t = abs( sin( theta ) );
|
|
float cos_t = abs( cos( theta ) );
|
|
rad = pow( abs( rad ), 1.4 );
|
|
rad = rad_max * ( rad + ( ( sin_t > cos_t ) ? rad - sin_t * rad : rad - cos_t * rad ) );
|
|
|
|
}
|
|
|
|
return rad - dist;
|
|
|
|
}
|
|
|
|
struct Cell {
|
|
|
|
// grid sample positions
|
|
vec2 normal;
|
|
vec2 p1;
|
|
vec2 p2;
|
|
vec2 p3;
|
|
vec2 p4;
|
|
float samp2;
|
|
float samp1;
|
|
float samp3;
|
|
float samp4;
|
|
|
|
};
|
|
|
|
vec4 getSample( vec2 point ) {
|
|
|
|
// multi-sampled point
|
|
vec4 tex = texture2D( tDiffuse, vec2( point.x / width, point.y / height ) );
|
|
float base = rand( vec2( floor( point.x ), floor( point.y ) ) ) * PI2;
|
|
float step = PI2 / float( samples );
|
|
float dist = radius * 0.66;
|
|
|
|
for ( int i = 0; i < samples; ++i ) {
|
|
|
|
float r = base + step * float( i );
|
|
vec2 coord = point + vec2( cos( r ) * dist, sin( r ) * dist );
|
|
tex += texture2D( tDiffuse, vec2( coord.x / width, coord.y / height ) );
|
|
|
|
}
|
|
|
|
tex /= float( samples ) + 1.0;
|
|
return tex;
|
|
|
|
}
|
|
|
|
float getDotColour( Cell c, vec2 p, int channel, float angle, float aa ) {
|
|
|
|
// get colour for given point
|
|
float dist_c_1, dist_c_2, dist_c_3, dist_c_4, res;
|
|
|
|
if ( channel == 0 ) {
|
|
|
|
c.samp1 = getSample( c.p1 ).r;
|
|
c.samp2 = getSample( c.p2 ).r;
|
|
c.samp3 = getSample( c.p3 ).r;
|
|
c.samp4 = getSample( c.p4 ).r;
|
|
|
|
} else if (channel == 1) {
|
|
|
|
c.samp1 = getSample( c.p1 ).g;
|
|
c.samp2 = getSample( c.p2 ).g;
|
|
c.samp3 = getSample( c.p3 ).g;
|
|
c.samp4 = getSample( c.p4 ).g;
|
|
|
|
} else {
|
|
|
|
c.samp1 = getSample( c.p1 ).b;
|
|
c.samp3 = getSample( c.p3 ).b;
|
|
c.samp2 = getSample( c.p2 ).b;
|
|
c.samp4 = getSample( c.p4 ).b;
|
|
|
|
}
|
|
|
|
dist_c_1 = distanceToDotRadius( c.samp1, c.p1, c.normal, p, angle, radius );
|
|
dist_c_2 = distanceToDotRadius( c.samp2, c.p2, c.normal, p, angle, radius );
|
|
dist_c_3 = distanceToDotRadius( c.samp3, c.p3, c.normal, p, angle, radius );
|
|
dist_c_4 = distanceToDotRadius( c.samp4, c.p4, c.normal, p, angle, radius );
|
|
res = ( dist_c_1 > 0.0 ) ? clamp( dist_c_1 / aa, 0.0, 1.0 ) : 0.0;
|
|
res += ( dist_c_2 > 0.0 ) ? clamp( dist_c_2 / aa, 0.0, 1.0 ) : 0.0;
|
|
res += ( dist_c_3 > 0.0 ) ? clamp( dist_c_3 / aa, 0.0, 1.0 ) : 0.0;
|
|
res += ( dist_c_4 > 0.0 ) ? clamp( dist_c_4 / aa, 0.0, 1.0 ) : 0.0;
|
|
res = clamp( res, 0.0, 1.0 );
|
|
|
|
return res;
|
|
|
|
}
|
|
|
|
Cell getReferenceCell( vec2 p, vec2 origin, float grid_angle, float step ) {
|
|
|
|
// get containing cell
|
|
Cell c;
|
|
|
|
// calc grid
|
|
vec2 n = vec2( cos( grid_angle ), sin( grid_angle ) );
|
|
float threshold = step * 0.5;
|
|
float dot_normal = n.x * ( p.x - origin.x ) + n.y * ( p.y - origin.y );
|
|
float dot_line = -n.y * ( p.x - origin.x ) + n.x * ( p.y - origin.y );
|
|
vec2 offset = vec2( n.x * dot_normal, n.y * dot_normal );
|
|
float offset_normal = mod( hypot( offset.x, offset.y ), step );
|
|
float normal_dir = ( dot_normal < 0.0 ) ? 1.0 : -1.0;
|
|
float normal_scale = ( ( offset_normal < threshold ) ? -offset_normal : step - offset_normal ) * normal_dir;
|
|
float offset_line = mod( hypot( ( p.x - offset.x ) - origin.x, ( p.y - offset.y ) - origin.y ), step );
|
|
float line_dir = ( dot_line < 0.0 ) ? 1.0 : -1.0;
|
|
float line_scale = ( ( offset_line < threshold ) ? -offset_line : step - offset_line ) * line_dir;
|
|
|
|
// get closest corner
|
|
c.normal = n;
|
|
c.p1.x = p.x - n.x * normal_scale + n.y * line_scale;
|
|
c.p1.y = p.y - n.y * normal_scale - n.x * line_scale;
|
|
|
|
// scatter
|
|
if ( scatter != 0.0 ) {
|
|
|
|
float off_mag = scatter * threshold * 0.5;
|
|
float off_angle = rand( vec2( floor( c.p1.x ), floor( c.p1.y ) ) ) * PI2;
|
|
c.p1.x += cos( off_angle ) * off_mag;
|
|
c.p1.y += sin( off_angle ) * off_mag;
|
|
|
|
}
|
|
|
|
// find corners
|
|
float normal_step = normal_dir * ( ( offset_normal < threshold ) ? step : -step );
|
|
float line_step = line_dir * ( ( offset_line < threshold ) ? step : -step );
|
|
c.p2.x = c.p1.x - n.x * normal_step;
|
|
c.p2.y = c.p1.y - n.y * normal_step;
|
|
c.p3.x = c.p1.x + n.y * line_step;
|
|
c.p3.y = c.p1.y - n.x * line_step;
|
|
c.p4.x = c.p1.x - n.x * normal_step + n.y * line_step;
|
|
c.p4.y = c.p1.y - n.y * normal_step - n.x * line_step;
|
|
|
|
return c;
|
|
|
|
}
|
|
|
|
float blendColour( float a, float b, float t ) {
|
|
|
|
// blend colours
|
|
if ( blendingMode == BLENDING_LINEAR ) {
|
|
return blend( a, b, 1.0 - t );
|
|
} else if ( blendingMode == BLENDING_ADD ) {
|
|
return blend( a, min( 1.0, a + b ), t );
|
|
} else if ( blendingMode == BLENDING_MULTIPLY ) {
|
|
return blend( a, max( 0.0, a * b ), t );
|
|
} else if ( blendingMode == BLENDING_LIGHTER ) {
|
|
return blend( a, max( a, b ), t );
|
|
} else if ( blendingMode == BLENDING_DARKER ) {
|
|
return blend( a, min( a, b ), t );
|
|
} else {
|
|
return blend( a, b, 1.0 - t );
|
|
}
|
|
|
|
}
|
|
|
|
void main() {
|
|
|
|
if ( ! disable ) {
|
|
|
|
// setup
|
|
vec2 p = vec2( vUV.x * width, vUV.y * height );
|
|
vec2 origin = vec2( 0, 0 );
|
|
float aa = ( radius < 2.5 ) ? radius * 0.5 : 1.25;
|
|
|
|
// get channel samples
|
|
Cell cell_r = getReferenceCell( p, origin, rotateR, radius );
|
|
Cell cell_g = getReferenceCell( p, origin, rotateG, radius );
|
|
Cell cell_b = getReferenceCell( p, origin, rotateB, radius );
|
|
float r = getDotColour( cell_r, p, 0, rotateR, aa );
|
|
float g = getDotColour( cell_g, p, 1, rotateG, aa );
|
|
float b = getDotColour( cell_b, p, 2, rotateB, aa );
|
|
|
|
// blend with original
|
|
vec4 colour = texture2D( tDiffuse, vUV );
|
|
r = blendColour( r, colour.r, blending );
|
|
g = blendColour( g, colour.g, blending );
|
|
b = blendColour( b, colour.b, blending );
|
|
|
|
if ( greyscale ) {
|
|
r = g = b = (r + b + g) / 3.0;
|
|
}
|
|
|
|
gl_FragColor = vec4( r, g, b, 1.0 );
|
|
|
|
} else {
|
|
|
|
gl_FragColor = texture2D( tDiffuse, vUV );
|
|
|
|
}
|
|
|
|
}`
|
|
};
|
|
|
|
THREE.HalftoneShader = HalftoneShader;
|
|
|
|
} )();
|
|
|