LYGIA Shader Library

Dependencies:

• lygia/lighting/raymarch/map.glsl
• lygia/lighting/material/new.glsl

Use:

<float> castRay( in <vec3> pos, in <vec3> nor )

Check it on Github

#ifndef RAYMARCH_SAMPLES
#define RAYMARCH_SAMPLES 256
#endif

#ifndef RAYMARCH_MIN_DIST
#define RAYMARCH_MIN_DIST 0.1
#endif

#ifndef RAYMARCH_MAX_DIST
#define RAYMARCH_MAX_DIST 20.0
#endif

#ifndef RAYMARCH_MIN_HIT_DIST
#define RAYMARCH_MIN_HIT_DIST 0.00001 * t
#endif

#ifndef FNC_RAYMARCH_CAST
#define FNC_RAYMARCH_CAST

Material raymarchCast( in vec3 ro, in vec3 rd ) {
    float tmin = RAYMARCH_MIN_DIST;
    float tmax = RAYMARCH_MAX_DIST;

    float t = tmin;
    Material m = materialNew();
    m.valid = false;
    for (int i = 0; i < RAYMARCH_SAMPLES; i++) {
        Material res = RAYMARCH_MAP_FNC(ro + rd * t);
        if (res.sdf < RAYMARCH_MIN_HIT_DIST || t > tmax) 
            break;
        m = res;
        t += res.sdf;
    }

    #if defined(RAYMARCH_BACKGROUND) || defined(RAYMARCH_FLOOR)
    if ( t > tmax )
        m.valid = false;
    #endif

    m.sdf = t;
    return m;
}

#endif

Dependencies:

• lygia/lighting/raymarch/map.glsl
• lygia/lighting/material/new.glsl

Use:

<float> castRay( in <float3> pos, in <float3> nor )

Check it on Github

#ifndef RAYMARCH_SAMPLES
#define RAYMARCH_SAMPLES 256
#endif

#ifndef RAYMARCH_MIN_DIST
#define RAYMARCH_MIN_DIST 0.1
#endif

#ifndef RAYMARCH_MAX_DIST
#define RAYMARCH_MAX_DIST 20.0
#endif

#ifndef RAYMARCH_MIN_HIT_DIST
#define RAYMARCH_MIN_HIT_DIST 0.00001 * t
#endif

#ifndef FNC_RAYMARCH_CAST
#define FNC_RAYMARCH_CAST

Material raymarchCast( in float3 ro, in float3 rd ) {
    float tmin = RAYMARCH_MIN_DIST;
    float tmax = RAYMARCH_MAX_DIST;

    float t = tmin;
    Material m = materialNew();
    m.valid = false;
    for (int i = 0; i < RAYMARCH_SAMPLES; i++) {
        Material res = RAYMARCH_MAP_FNC(ro + rd * t);
        if (res.sdf < RAYMARCH_MIN_HIT_DIST || t > tmax) 
            break;
        m = res;
        t += res.sdf;
    }

    #if defined(RAYMARCH_BACKGROUND) || defined(RAYMARCH_FLOOR)
    if ( t > tmax )
        m.valid = false;
    #endif

    m.sdf = t;
    return m;
}

#endif

Check it on Github

// #include "map.wgls"

fn raymarchCast(ro: vec3f, rd: vec3f ) -> f32 {
    var dist = -1.0;
    var t = -1.0;
    for (var i = 0; i < 120 && t < 100.0; i++) {
        let h = map( ro + rd * t );
        if (abs(h) < (0.001 * t)) { 
            dist = t; 
            break;
        }
        t += h;
    }
    return dist;
}

Dependencies:

• lygia/lighting/raymarch/map.glsl

Use:

<float> castRay( in <float3> pos, in <float3> nor )

Check it on Github

#ifndef RAYMARCH_SAMPLES
#define RAYMARCH_SAMPLES 64
#endif

#ifndef RAYMARCH_MAP_FNC
#define RAYMARCH_MAP_FNC(POS) raymarchMap(POS)
#endif

#ifndef RAYMARCH_MAP_TYPE
#define RAYMARCH_MAP_TYPE float4
#endif

#ifndef RAYMARCH_MAP_DISTANCE
#define RAYMARCH_MAP_DISTANCE w
#endif

#ifndef FNC_RAYMARCH_CAST
#define FNC_RAYMARCH_CAST

inline __host__ __device__ RAYMARCH_MAP_TYPE raymarchCast(const float3& ro, const float3& rd) {
    float tmin = 1.0;
    float tmax = 20.0;

// #if defined(RAYMARCH_FLOOR)
//     float tp1 = (0.0-ro.y)/rd.y; if( tp1>0.0 ) tmax = min( tmax, tp1 );
//     float tp2 = (1.6-ro.y)/rd.y; if( tp2>0.0 ) { if( ro.y>1.6 ) tmin = max( tmin, tp2 );
//                                                  else           tmax = min( tmax, tp2 ); }
// #endif

    float t = tmin;
    RAYMARCH_MAP_TYPE m = make_float4(-1.0f);
    for ( int i = 0; i < RAYMARCH_SAMPLES; i++ ) {
        float precis = 0.00001*t;
        RAYMARCH_MAP_TYPE res = RAYMARCH_MAP_FNC( ro + rd * t );
        if ( res.w < precis || t > tmax ) 
            break;
        t += res.w;
        m = res;
    }

    #if defined(RAYMARCH_BACKGROUND) || defined(RAYMARCH_FLOOR)
    if ( t > tmax ) 
        m = make_float4(-1.0);
    #endif

    m.RAYMARCH_MAP_DISTANCE = t;
    return m;
}

#endif