Ray Tracing Archives

URL: http://glslsandbox.com/e#22751.0

//--------------------------------------------------------------------------------------------
// Simple GPU Ray Tracer
// By: Brandon Fogerty
// bfogerty at gmail dot com
// xdpixel.com
//--------------------------------------------------------------------------------------------

#ifdef GL_ES
precision mediump float;
#endif

uniform float time;
uniform vec2 mouse;
uniform vec2 resolution;

//--------------------------------------------------------------------------------------------
// Begin Region: Defines
//--------------------------------------------------------------------------------------------
#define PrimitiveType_None          0.0
#define PrimitiveType_Sphere        1.0
#define PrimitiveType_Plane         2.0

#define MAX_SPHERES                 5
#define MAX_PLANES                  6

#define TimeValue                   time
#define ResolutionValue             resolution
#define Epsilon                     0.000001

#define MaterialIndex0              0
#define MaterialIndex1              1
#define MaterialIndex2              2
#define MaterialIndex3              3
#define MaterialIndex4              4
#define MaterialIndex5              5
#define MaterialIndex6              6
#define MaterialIndex7              7
#define MaterialIndex8              8
#define MaterialIndex9              9
#define MaterialIndex10             10
//--------------------------------------------------------------------------------------------
// End Region
//--------------------------------------------------------------------------------------------

//--------------------------------------------------------------------------------------------
// Begin Region: Data Structures
//--------------------------------------------------------------------------------------------
struct Ray
{
    vec3 origin;
    vec3 direction;
};

struct Material
{
    vec3 diffuseColor;
    vec3 specularColor;
    float specularIntensity;

    float receiveShadow;
    float shadowCasterIntensity;
    
    float reflectionIntensity;

    float refractionIndex;
    float refractionIntensity;
};

struct SphereParms
{
    vec3 position;
    float radius;
    int materialIndex;
    int lightVisualizer;
    int id;
};

struct PlaneParams
{
    vec3 pointOnPlane;
    vec3 normal;
    int materialIndex;
    int id;
};

struct HitInfo
{
    vec3 position;
    vec3 normal;
    vec3 rayDir;
    float t;
    float dist;
   
    int materialIndex;

    int lightVisualizer;
  
    float primitiveType;
    float hit;
    int id;
};

//--------------------------------------------------------------------------------------------
// End Region
//--------------------------------------------------------------------------------------------

//--------------------------------------------------------------------------------------------
// Begin Region: Global Variables
//--------------------------------------------------------------------------------------------
SphereParms spheres[MAX_SPHERES];
HitInfo sphereHitInfos[MAX_SPHERES];
PlaneParams planes[MAX_PLANES];
HitInfo planeHitInfos[MAX_PLANES];
Material materials[11];
vec3 lightPos;
//--------------------------------------------------------------------------------------------
// End Region
//--------------------------------------------------------------------------------------------

Material getMaterial( int materialIndex )
{
    // GLSL does not allow variables to be used as indicies into an array.
    // This is a work around but not as efficient as it could be...
    if( materialIndex == MaterialIndex0 ) return materials[0];
    if( materialIndex == MaterialIndex1 ) return materials[1];
    if( materialIndex == MaterialIndex2 ) return materials[2];
    if( materialIndex == MaterialIndex3 ) return materials[3];
    if( materialIndex == MaterialIndex4 ) return materials[4];
    if( materialIndex == MaterialIndex5 ) return materials[5];
    if( materialIndex == MaterialIndex6 ) return materials[6];
    if( materialIndex == MaterialIndex7 ) return materials[7];
    if( materialIndex == MaterialIndex8 ) return materials[8];
    if( materialIndex == MaterialIndex9 ) return materials[9];
   
    return materials[10];
}

//--------------------------------------------------------------------------------------------
vec3 checkerBoardTexture( vec3 hitPos )
{
     vec2 p = floor( hitPos.xz * 1.0 );
     float s = mod( p.x + p.y, 2.0 );
     vec3 c = vec3( 0.4 ) * s;
     c = mix( c, vec3( 0.9 ), hitPos.z / 30.0 );
  
     return c;
}

//--------------------------------------------------------------------------------------------
void sphere( Ray ray, SphereParms sphereParams, inout HitInfo hitInfo )
{
    hitInfo.primitiveType = PrimitiveType_None;
    hitInfo.t = -1.0;
    hitInfo.hit = 0.0;

    vec3 newO = ray.origin - sphereParams.position;
    float b = 2.0 * dot( newO, ray.direction );
    float c = dot( newO, newO ) - (sphereParams.radius*sphereParams.radius);

    float h = b*b - (4.0*c);
    if( h < 0.0 ) return;
    float t = (-b - sqrt( h ) ) / 2.0;

    if ( t < Epsilon ) return;
   
    hitInfo.position = ray.origin + ray.direction * t;
    hitInfo.normal = normalize( ( hitInfo.position - sphereParams.position ) / sphereParams.radius );
    hitInfo.t = t;
    hitInfo.dist = length( hitInfo.position - ray.origin );
    hitInfo.rayDir = ray.direction;
    hitInfo.materialIndex = sphereParams.materialIndex;
    hitInfo.lightVisualizer = sphereParams.lightVisualizer;
    hitInfo.primitiveType = PrimitiveType_Sphere;
    hitInfo.id = sphereParams.id;
    hitInfo.hit = 1.0;
}

//--------------------------------------------------------------------------------------------
void plane( Ray ray, PlaneParams planeParams, inout HitInfo hitInfo )
{
    hitInfo.primitiveType = PrimitiveType_None;
    hitInfo.t = -1.0;
    hitInfo.hit = 0.0;

    float d = dot( planeParams.pointOnPlane, planeParams.normal );
    float t = ( d - dot( ray.origin, planeParams.normal ) ) / dot( ray.direction, planeParams.normal );

    if( t < 0.00 )
    {
        return;
    }

    hitInfo.position = ray.origin + ray.direction * t;
    hitInfo.normal = normalize( planeParams.normal );
    hitInfo.t = t;
    hitInfo.dist = length( hitInfo.position - ray.origin );
    hitInfo.rayDir = ray.direction;
    hitInfo.materialIndex = planeParams.materialIndex;
    hitInfo.lightVisualizer = 0;
    hitInfo.primitiveType = PrimitiveType_Plane;
    hitInfo.id = planeParams.id;
    hitInfo.hit = 1.0;
}

//--------------------------------------------------------------------------------------------
HitInfo intersect( Ray ray )
{
    HitInfo hitInfo;
    hitInfo.primitiveType = PrimitiveType_None;
   
    for( int i = 0; i < MAX_SPHERES; ++i )
    {
        sphere( ray, spheres[i], sphereHitInfos[i] );
      
        if( sphereHitInfos[i].primitiveType > PrimitiveType_None )
        {
            if(  sphereHitInfos[i].dist <  hitInfo.dist || hitInfo.primitiveType <= PrimitiveType_None )
            {
                hitInfo = sphereHitInfos[i];
            }
        }
    }
  
    for( int i = 0; i < MAX_PLANES; ++i )
    {
        plane( ray, planes[i], planeHitInfos[i] );
      
        if( planeHitInfos[i].primitiveType > PrimitiveType_None )
        {
            if(  planeHitInfos[i].dist <  hitInfo.dist || hitInfo.primitiveType <= PrimitiveType_None )
            {           
                hitInfo = planeHitInfos[i];
            }
        }
    }
   
    return hitInfo;
}

//--------------------------------------------------------------------------------------------
void initializeMaterials()
{

    materials[0].diffuseColor = vec3( 1.0, 1.0, 0.0 );
    materials[0].specularColor = vec3( 1.0 );
    materials[0].specularIntensity = 10.0;
    materials[0].shadowCasterIntensity = 1.0;
    materials[0].reflectionIntensity = 0.00;
    materials[0].refractionIndex = 1.0;
    materials[0].refractionIntensity = 0.00;

    materials[1].diffuseColor = vec3( 1.0, 1.4, 1.0 );
    materials[1].specularColor = vec3( 1.0 );
    materials[1].specularIntensity = 10.0;
    materials[1].shadowCasterIntensity = 0.5;
    materials[1].reflectionIntensity = 0.00;
    materials[1].refractionIndex = 1.0;
    materials[1].refractionIntensity = 0.00;

    materials[2].diffuseColor = vec3( 1.0, 0.4, 1.0 );
    materials[2].specularColor = vec3( 1.0 );
    materials[2].specularIntensity = 20.0;
    materials[2].shadowCasterIntensity = 0.5;
    materials[2].reflectionIntensity = 0.7;
    materials[2].refractionIndex = 1.0;
    materials[2].refractionIntensity = 0.00;

    materials[3].diffuseColor = vec3( 0.0, 1.0, 1.4 );
    materials[3].specularColor = vec3( 1.0 );
    materials[3].specularIntensity = 10.0;
    materials[3].shadowCasterIntensity = 0.5;
    materials[3].reflectionIntensity = 0.00;
    materials[3].refractionIndex = 1.0;
    materials[3].refractionIntensity = 0.00;

    materials[4].diffuseColor = vec3( 0.8 );
    materials[4].specularColor = vec3( 1.0 );
    materials[4].specularIntensity = 10.0;
    materials[4].shadowCasterIntensity = 1.0;
    materials[4].reflectionIntensity = 0.00;
    materials[4].refractionIndex = 1.0;
    materials[4].refractionIntensity = 0.00;

    materials[5].diffuseColor = vec3( 1.0, 0.0, 0.0 );
    materials[5].specularColor = vec3( 1.0 );
    materials[5].specularIntensity = 10.0;
    materials[5].shadowCasterIntensity = 1.0;
    materials[5].reflectionIntensity = 0.00;
    materials[5].refractionIndex = 1.0;
    materials[5].refractionIntensity = 0.00;
   
    materials[6].diffuseColor = vec3( 0.0, 0.0, 1.0 );
    materials[6].specularColor = vec3( 1.0 );
    materials[6].specularIntensity = 10.0;
    materials[6].shadowCasterIntensity = 1.0;
    materials[6].reflectionIntensity = 0.00;
    materials[6].refractionIndex = 1.0;
    materials[6].refractionIntensity = 0.00;
   
    materials[7].diffuseColor = vec3( 0.0, 1.0, 0.0 );
    materials[7].specularColor = vec3( 1.0 );
    materials[7].specularIntensity = 10.0;
    materials[7].shadowCasterIntensity = 1.0;
    materials[7].reflectionIntensity = 0.00;
    materials[7].refractionIndex = 1.0;
    materials[7].refractionIntensity = 0.00;
   
    materials[8].diffuseColor = vec3( 0.0, 1.0, 1.0 );
    materials[8].specularColor = vec3( 1.0 );
    materials[8].specularIntensity = 10.0;
    materials[8].shadowCasterIntensity = 1.0;
    materials[8].reflectionIntensity = 0.00;
    materials[8].refractionIndex = 1.0;
    materials[8].refractionIntensity = 0.00;
   
    materials[9].diffuseColor = vec3( 1.0, 1.0, 0.0 );
    materials[9].specularColor = vec3( 1.0 );
    materials[9].specularIntensity = 10.0;
    materials[9].shadowCasterIntensity = 1.0;
    materials[9].reflectionIntensity = 0.00;
    materials[9].refractionIndex = 1.0;
    materials[9].refractionIntensity = 0.00;

    materials[10].diffuseColor = vec3( 0.3, 0.0, 1.0 );
    materials[10].specularColor = vec3( 0.0 );
    materials[10].specularIntensity = 1.0;
    materials[10].shadowCasterIntensity = 0.5;
    materials[10].reflectionIntensity = 0.00;
    materials[10].refractionIndex = 1.0;
    materials[10].refractionIntensity = 1.0;
}

//--------------------------------------------------------------------------------------------
void initializeScene()
{
    int id = -1;
    lightPos = vec3( 0.0, 3.0, 9.0 );
  
    // Light Visualizer
    spheres[0].position = lightPos;
    spheres[0].radius = 0.5;
    spheres[0].materialIndex = 0;
    spheres[0].lightVisualizer = 1;
    spheres[0].id = ++id;
  
    spheres[1].position = vec3( -5.0, 1.0, -3.0 );
    spheres[1].radius = 1.0;
    spheres[1].materialIndex = 1;
    spheres[1].id = ++id;

    spheres[2].position = vec3( 0.0, 1.0, 1.0 );
    spheres[2].radius = 1.0;
    spheres[2].materialIndex = 2;
    spheres[2].id = ++id;

    spheres[3].position = vec3( 5.0, 1.0, -3.0 );
    spheres[3].radius = 1.0;
    spheres[3].materialIndex = 3;
    spheres[3].id = ++id;

    spheres[4].position = vec3( 0.0, 1.0, 1.0 );
    spheres[4].radius = 1.0;
    spheres[4].materialIndex = 10;
    spheres[4].id = ++id;

    planes[0].pointOnPlane = vec3( 0.0, 0.0, 0.0 );
    planes[0].normal = vec3( 0.0, 1.0, 0.0 );
    planes[0].materialIndex = 4;
    planes[0].id = ++id;
   
    planes[1].pointOnPlane = vec3( -10.0, 0.0, 0.0 );
    planes[1].normal = vec3( 1.0, 0.0, 0.0 );
    planes[1].materialIndex = 5;
    planes[1].id = ++id;
   
    planes[2].pointOnPlane = vec3( 10.0, 0.0, 0.0 );
    planes[2].normal = vec3( -1.0, 0.0, 0.0 );
    planes[2].materialIndex = 6;
    planes[2].id = ++id;
   
    planes[3].pointOnPlane = vec3( 0.0, 0.0, -10.0 );
    planes[3].normal = vec3( 0.0, 0.0, 1.0 );
    planes[3].materialIndex = 7;
    planes[3].id = ++id;
   
    planes[4].pointOnPlane = vec3( 0.0, 15.0, 0.0 );
    planes[4].normal = vec3( 0.0, -1.0, 0.0 );
    planes[4].materialIndex = 8;
    planes[4].id = ++id;
   
    planes[5].pointOnPlane = vec3( 0.0, 0.0, 25.0 );
    planes[5].normal = vec3( 0.0, 0.0, -1.0 );
    planes[5].materialIndex = 9;
    planes[5].id = ++id;
}

//--------------------------------------------------------------------------------------------
void onAnimateScene()
{
    float animationTime = TimeValue * 0.5;

    lightPos = vec3( sin(TimeValue* 0.3)*5.0, 4.3, cos(TimeValue * 0.3)*10.0 );
    spheres[0].position = lightPos;
   
    spheres[2].position.x += sin( animationTime * 1.0 ) * 3.0;
    spheres[2].position.y += abs( sin( animationTime * 4.0 ) * 2.0 );
    spheres[2].position.z += sin( cos( animationTime)  *    3.0 ) * 2.0;

    spheres[4].position.x -= sin( animationTime * 1.0 ) * 3.0;
    spheres[4].position.y += abs( sin( animationTime * 5.3 ) * 2.0 );
    spheres[4].position.z -= sin( cos( animationTime)  *    3.0 ) * 2.0;
}

//--------------------------------------------------------------------------------------------
vec3 getObjectsBaseColor(HitInfo hitInfo)
{
    Material mat = getMaterial(hitInfo.materialIndex);
    if( hitInfo.id == 5 || hitInfo.id == 9 )
    {
       
        return checkerBoardTexture( hitInfo.position ) * mat.diffuseColor;
    }

    return mat.diffuseColor;
}

//--------------------------------------------------------------------------------------------
vec3 calculateReflection( vec3 viewDir, HitInfo hitInfo )
{   
    Material objectMaterial = getMaterial(hitInfo.materialIndex);
    if( objectMaterial.reflectionIntensity <= 0.00 )
    {
        return vec3( 0.0 );
    }

    Ray reflectionRay;
    reflectionRay.direction = normalize( reflect( hitInfo.rayDir, hitInfo.normal ) );
    reflectionRay.origin = hitInfo.position + hitInfo.normal * Epsilon;
   
    HitInfo rHitInfo = intersect( reflectionRay );
    vec3 color = getObjectsBaseColor(rHitInfo) * objectMaterial.reflectionIntensity;
   
    return color;
}

//--------------------------------------------------------------------------------------------
vec3 calculateRefraction( vec3 viewDir, HitInfo hitInfo )
{   
    Material objectMaterial = getMaterial(hitInfo.materialIndex);
    if( objectMaterial.refractionIntensity <= 0.00 )
    {
        return vec3( 0.0 );
    }

    Ray refractionRay;
    refractionRay.direction = normalize( refract( hitInfo.rayDir, hitInfo.normal, objectMaterial.refractionIndex ) );
    refractionRay.origin = hitInfo.position - hitInfo.normal * Epsilon;
   
    HitInfo rHitInfo = intersect( refractionRay );
    for( int i = 0; i < 10; ++i )
    {
        if( rHitInfo.id == hitInfo.id )
        {
            refractionRay.origin = rHitInfo.position - rHitInfo.normal * Epsilon;
            rHitInfo = intersect( refractionRay );
        }
        else
        {
            break;
        }
    }
    
    vec3 color = getObjectsBaseColor(rHitInfo) * objectMaterial.refractionIntensity;
   
    return color;
}

//--------------------------------------------------------------------------------------------
float calculateShadow( vec3 lightDir, HitInfo hitInfo )
{
    Ray shadowRay;
    shadowRay.direction = normalize( lightDir );
    shadowRay.origin = hitInfo.position + (shadowRay.direction * 0.001);
    HitInfo shadowHitInfo = intersect( shadowRay );
    Material mat = getMaterial(shadowHitInfo.materialIndex);
    return clamp( mat.shadowCasterIntensity, 0.00, 1.0 );
}

//--------------------------------------------------------------------------------------------
void main(void)
{
    float mx = (mouse.x * 2.0 - 1.0) * (ResolutionValue.x / ResolutionValue.y);
    float my = (mouse.y * 2.0 - 1.0);
    vec2 mouseOffset = vec2( mx, my );

    vec2 uv = gl_FragCoord.xy / ResolutionValue.x;
    vec2 uvp = (uv * 2.0 - 1.0) + mouseOffset;

    Ray ray;
    ray.origin = vec3( 0.0, 5.0, 10.0 );
    ray.direction = normalize( vec3( uvp, -1.0 ) );

    initializeMaterials();
    initializeScene();

    onAnimateScene();

    HitInfo hitInfo = intersect( ray );

    vec3 c = vec3( 0.9 );
    if( hitInfo.primitiveType <= PrimitiveType_None )
    {
        gl_FragColor = vec4( c, 1.0 );
        return;
    }

    vec3 lightDir = normalize( lightPos - hitInfo.position );

    float shadowFactor = calculateShadow( lightDir, hitInfo );

    // Calculate Lighting
    Material mat = getMaterial( hitInfo.materialIndex );
    float diffuseFactor = clamp( dot( hitInfo.normal, lightDir ), 0.00, 1.00 );
    vec3 reflectionVector = normalize( reflect( lightDir, hitInfo.normal ) );
    vec3 cameraToSurface = ray.direction;
    float specularFactor = pow( clamp( dot( reflectionVector, cameraToSurface ), 0.00, 1.0 ), mat.specularIntensity );

    vec3 baseColor = getObjectsBaseColor(hitInfo);
    vec3 reflection = calculateReflection( ray.direction, hitInfo );
    vec3 refraction = calculateRefraction( ray.direction, hitInfo );

    vec3 diffuse = (baseColor + reflection + refraction) * diffuseFactor;
    vec3 specular = (mat.specularColor * specularFactor) * step( 1.0, shadowFactor );
    c = (diffuse + specular) * shadowFactor;

    gl_FragColor = vec4( c, 1.0 );
}

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//--------------------------------------------------------------------------------------------

// Simple GPU Ray Tracer

// By: Brandon Fogerty

// bfogerty at gmail dot com

// xdpixel.com

//--------------------------------------------------------------------------------------------

#ifdef GL_ES

precision mediump float;

#endif

uniform float time;

uniform vec2 mouse;

uniform vec2 resolution;

//--------------------------------------------------------------------------------------------

// Begin Region: Defines

//--------------------------------------------------------------------------------------------

#define PrimitiveType_None 0.0

#define PrimitiveType_Sphere 1.0

#define PrimitiveType_Plane 2.0

#define MAX_SPHERES 5

#define MAX_PLANES 6

#define TimeValue time

#define ResolutionValue resolution

#define Epsilon 0.000001

#define MaterialIndex0 0

#define MaterialIndex1 1

#define MaterialIndex2 2

#define MaterialIndex3 3

#define MaterialIndex4 4

#define MaterialIndex5 5

#define MaterialIndex6 6

#define MaterialIndex7 7

#define MaterialIndex8 8

#define MaterialIndex9 9

#define MaterialIndex10 10

//--------------------------------------------------------------------------------------------

// End Region

//--------------------------------------------------------------------------------------------

// Begin Region: Data Structures

//--------------------------------------------------------------------------------------------

struct Ray

{

vec3 origin;

vec3 direction;

};

struct Material

{

vec3 diffuseColor;

vec3 specularColor;

float specularIntensity;

float receiveShadow;

float shadowCasterIntensity;

float reflectionIntensity;

float refractionIndex;

float refractionIntensity;

};

struct SphereParms

{

vec3 position;

float radius;

int materialIndex;

int lightVisualizer;

int id;

};

struct PlaneParams

{

vec3 pointOnPlane;

vec3 normal;

int materialIndex;

int id;

};

struct HitInfo

{

vec3 position;

vec3 normal;

vec3 rayDir;

float t;

float dist;

int materialIndex;

int lightVisualizer;

float primitiveType;

float hit;

int id;

};

//--------------------------------------------------------------------------------------------

// End Region

//--------------------------------------------------------------------------------------------

// Begin Region: Global Variables

//--------------------------------------------------------------------------------------------

SphereParms spheres[MAX_SPHERES];

HitInfo sphereHitInfos[MAX_SPHERES];

PlaneParams planes[MAX_PLANES];

HitInfo planeHitInfos[MAX_PLANES];

Material materials[11];

vec3 lightPos;

//--------------------------------------------------------------------------------------------

// End Region

//--------------------------------------------------------------------------------------------

Material getMaterial( int materialIndex )

{

// GLSL does not allow variables to be used as indicies into an array.

// This is a work around but not as efficient as it could be...

if( materialIndex == MaterialIndex0 ) return materials[0];

if( materialIndex == MaterialIndex1 ) return materials[1];

if( materialIndex == MaterialIndex2 ) return materials[2];

if( materialIndex == MaterialIndex3 ) return materials[3];

if( materialIndex == MaterialIndex4 ) return materials[4];

if( materialIndex == MaterialIndex5 ) return materials[5];

if( materialIndex == MaterialIndex6 ) return materials[6];

if( materialIndex == MaterialIndex7 ) return materials[7];

if( materialIndex == MaterialIndex8 ) return materials[8];

if( materialIndex == MaterialIndex9 ) return materials[9];

return materials[10];

}

//--------------------------------------------------------------------------------------------

vec3 checkerBoardTexture( vec3 hitPos )

{

vec2 p = floor( hitPos.xz * 1.0 );

float s = mod( p.x + p.y, 2.0 );

vec3 c = vec3( 0.4 ) * s;

c = mix( c, vec3( 0.9 ), hitPos.z / 30.0 );

return c;

}

//--------------------------------------------------------------------------------------------

void sphere( Ray ray, SphereParms sphereParams, inout HitInfo hitInfo )

{

hitInfo.primitiveType = PrimitiveType_None;

hitInfo.t = -1.0;

hitInfo.hit = 0.0;

vec3 newO = ray.origin - sphereParams.position;

float b = 2.0 * dot( newO, ray.direction );

float c = dot( newO, newO ) - (sphereParams.radius*sphereParams.radius);

float h = b*b - (4.0*c);

if( h < 0.0 ) return;

float t = (-b - sqrt( h ) ) / 2.0;

if ( t < Epsilon ) return;

hitInfo.position = ray.origin + ray.direction * t;

hitInfo.normal = normalize( ( hitInfo.position - sphereParams.position ) / sphereParams.radius );

hitInfo.t = t;

hitInfo.dist = length( hitInfo.position - ray.origin );

hitInfo.rayDir = ray.direction;

hitInfo.materialIndex = sphereParams.materialIndex;

hitInfo.lightVisualizer = sphereParams.lightVisualizer;

hitInfo.primitiveType = PrimitiveType_Sphere;

hitInfo.id = sphereParams.id;

hitInfo.hit = 1.0;

}

//--------------------------------------------------------------------------------------------

void plane( Ray ray, PlaneParams planeParams, inout HitInfo hitInfo )

{

hitInfo.primitiveType = PrimitiveType_None;

hitInfo.t = -1.0;

hitInfo.hit = 0.0;

float d = dot( planeParams.pointOnPlane, planeParams.normal );

float t = ( d - dot( ray.origin, planeParams.normal ) ) / dot( ray.direction, planeParams.normal );

if( t < 0.00 )

{

return;

}

hitInfo.position = ray.origin + ray.direction * t;

hitInfo.normal = normalize( planeParams.normal );

hitInfo.t = t;

hitInfo.dist = length( hitInfo.position - ray.origin );

hitInfo.rayDir = ray.direction;

hitInfo.materialIndex = planeParams.materialIndex;

hitInfo.lightVisualizer = 0;

hitInfo.primitiveType = PrimitiveType_Plane;

hitInfo.id = planeParams.id;

hitInfo.hit = 1.0;

}

//--------------------------------------------------------------------------------------------

HitInfo intersect( Ray ray )

{

HitInfo hitInfo;

hitInfo.primitiveType = PrimitiveType_None;

for( int i = 0; i < MAX_SPHERES; ++i )

{

sphere( ray, spheres[i], sphereHitInfos[i] );

if( sphereHitInfos[i].primitiveType > PrimitiveType_None )

{

if( sphereHitInfos[i].dist < hitInfo.dist || hitInfo.primitiveType <= PrimitiveType_None )

{

hitInfo = sphereHitInfos[i];

}

for( int i = 0; i < MAX_PLANES; ++i )

{

plane( ray, planes[i], planeHitInfos[i] );

if( planeHitInfos[i].primitiveType > PrimitiveType_None )

{

if( planeHitInfos[i].dist < hitInfo.dist || hitInfo.primitiveType <= PrimitiveType_None )

{

hitInfo = planeHitInfos[i];

}

return hitInfo;

}

//--------------------------------------------------------------------------------------------

void initializeMaterials()

{

materials[0].diffuseColor = vec3( 1.0, 1.0, 0.0 );

materials[0].specularColor = vec3( 1.0 );

materials[0].specularIntensity = 10.0;

materials[0].shadowCasterIntensity = 1.0;

materials[0].reflectionIntensity = 0.00;

materials[0].refractionIndex = 1.0;

materials[0].refractionIntensity = 0.00;

materials[1].diffuseColor = vec3( 1.0, 1.4, 1.0 );

materials[1].specularColor = vec3( 1.0 );

materials[1].specularIntensity = 10.0;

materials[1].shadowCasterIntensity = 0.5;

materials[1].reflectionIntensity = 0.00;

materials[1].refractionIndex = 1.0;

materials[1].refractionIntensity = 0.00;

materials[2].diffuseColor = vec3( 1.0, 0.4, 1.0 );

materials[2].specularColor = vec3( 1.0 );

materials[2].specularIntensity = 20.0;

materials[2].shadowCasterIntensity = 0.5;

materials[2].reflectionIntensity = 0.7;

materials[2].refractionIndex = 1.0;

materials[2].refractionIntensity = 0.00;

materials[3].diffuseColor = vec3( 0.0, 1.0, 1.4 );

materials[3].specularColor = vec3( 1.0 );

materials[3].specularIntensity = 10.0;

materials[3].shadowCasterIntensity = 0.5;

materials[3].reflectionIntensity = 0.00;

materials[3].refractionIndex = 1.0;

materials[3].refractionIntensity = 0.00;

materials[4].diffuseColor = vec3( 0.8 );

materials[4].specularColor = vec3( 1.0 );

materials[4].specularIntensity = 10.0;

materials[4].shadowCasterIntensity = 1.0;

materials[4].reflectionIntensity = 0.00;

materials[4].refractionIndex = 1.0;

materials[4].refractionIntensity = 0.00;

materials[5].diffuseColor = vec3( 1.0, 0.0, 0.0 );

materials[5].specularColor = vec3( 1.0 );

materials[5].specularIntensity = 10.0;

materials[5].shadowCasterIntensity = 1.0;

materials[5].reflectionIntensity = 0.00;

materials[5].refractionIndex = 1.0;

materials[5].refractionIntensity = 0.00;

materials[6].diffuseColor = vec3( 0.0, 0.0, 1.0 );

materials[6].specularColor = vec3( 1.0 );

materials[6].specularIntensity = 10.0;

materials[6].shadowCasterIntensity = 1.0;

materials[6].reflectionIntensity = 0.00;

materials[6].refractionIndex = 1.0;

materials[6].refractionIntensity = 0.00;

materials[7].diffuseColor = vec3( 0.0, 1.0, 0.0 );

materials[7].specularColor = vec3( 1.0 );

materials[7].specularIntensity = 10.0;

materials[7].shadowCasterIntensity = 1.0;

materials[7].reflectionIntensity = 0.00;

materials[7].refractionIndex = 1.0;

materials[7].refractionIntensity = 0.00;

materials[8].diffuseColor = vec3( 0.0, 1.0, 1.0 );

materials[8].specularColor = vec3( 1.0 );

materials[8].specularIntensity = 10.0;

materials[8].shadowCasterIntensity = 1.0;

materials[8].reflectionIntensity = 0.00;

materials[8].refractionIndex = 1.0;

materials[8].refractionIntensity = 0.00;

materials[9].diffuseColor = vec3( 1.0, 1.0, 0.0 );

materials[9].specularColor = vec3( 1.0 );

materials[9].specularIntensity = 10.0;

materials[9].shadowCasterIntensity = 1.0;

materials[9].reflectionIntensity = 0.00;

materials[9].refractionIndex = 1.0;

materials[9].refractionIntensity = 0.00;

materials[10].diffuseColor = vec3( 0.3, 0.0, 1.0 );

materials[10].specularColor = vec3( 0.0 );

materials[10].specularIntensity = 1.0;

materials[10].shadowCasterIntensity = 0.5;

materials[10].reflectionIntensity = 0.00;

materials[10].refractionIndex = 1.0;

materials[10].refractionIntensity = 1.0;

}

//--------------------------------------------------------------------------------------------

void initializeScene()

{

int id = -1;

lightPos = vec3( 0.0, 3.0, 9.0 );

// Light Visualizer

spheres[0].position = lightPos;

spheres[0].radius = 0.5;

spheres[0].materialIndex = 0;

spheres[0].lightVisualizer = 1;

spheres[0].id = ++id;

spheres[1].position = vec3( -5.0, 1.0, -3.0 );

spheres[1].radius = 1.0;

spheres[1].materialIndex = 1;

spheres[1].id = ++id;

spheres[2].position = vec3( 0.0, 1.0, 1.0 );

spheres[2].radius = 1.0;

spheres[2].materialIndex = 2;

spheres[2].id = ++id;

spheres[3].position = vec3( 5.0, 1.0, -3.0 );

spheres[3].radius = 1.0;

spheres[3].materialIndex = 3;

spheres[3].id = ++id;

spheres[4].position = vec3( 0.0, 1.0, 1.0 );

spheres[4].radius = 1.0;

spheres[4].materialIndex = 10;

spheres[4].id = ++id;

planes[0].pointOnPlane = vec3( 0.0, 0.0, 0.0 );

planes[0].normal = vec3( 0.0, 1.0, 0.0 );

planes[0].materialIndex = 4;

planes[0].id = ++id;

planes[1].pointOnPlane = vec3( -10.0, 0.0, 0.0 );

planes[1].normal = vec3( 1.0, 0.0, 0.0 );

planes[1].materialIndex = 5;

planes[1].id = ++id;

planes[2].pointOnPlane = vec3( 10.0, 0.0, 0.0 );

planes[2].normal = vec3( -1.0, 0.0, 0.0 );

planes[2].materialIndex = 6;

planes[2].id = ++id;

planes[3].pointOnPlane = vec3( 0.0, 0.0, -10.0 );

planes[3].normal = vec3( 0.0, 0.0, 1.0 );

planes[3].materialIndex = 7;

planes[3].id = ++id;

planes[4].pointOnPlane = vec3( 0.0, 15.0, 0.0 );

planes[4].normal = vec3( 0.0, -1.0, 0.0 );

planes[4].materialIndex = 8;

planes[4].id = ++id;

planes[5].pointOnPlane = vec3( 0.0, 0.0, 25.0 );

planes[5].normal = vec3( 0.0, 0.0, -1.0 );

planes[5].materialIndex = 9;

planes[5].id = ++id;

}

//--------------------------------------------------------------------------------------------

void onAnimateScene()

{

float animationTime = TimeValue * 0.5;

lightPos = vec3( sin(TimeValue* 0.3)*5.0, 4.3, cos(TimeValue * 0.3)*10.0 );

spheres[0].position = lightPos;

spheres[2].position.x += sin( animationTime * 1.0 ) * 3.0;

spheres[2].position.y += abs( sin( animationTime * 4.0 ) * 2.0 );

spheres[2].position.z += sin( cos( animationTime) * 3.0 ) * 2.0;

spheres[4].position.x -= sin( animationTime * 1.0 ) * 3.0;

spheres[4].position.y += abs( sin( animationTime * 5.3 ) * 2.0 );

spheres[4].position.z -= sin( cos( animationTime) * 3.0 ) * 2.0;

}

//--------------------------------------------------------------------------------------------

vec3 getObjectsBaseColor(HitInfo hitInfo)

{

Material mat = getMaterial(hitInfo.materialIndex);

if( hitInfo.id == 5 || hitInfo.id == 9 )

{

return checkerBoardTexture( hitInfo.position ) * mat.diffuseColor;

}

return mat.diffuseColor;

}

//--------------------------------------------------------------------------------------------

vec3 calculateReflection( vec3 viewDir, HitInfo hitInfo )

{

Material objectMaterial = getMaterial(hitInfo.materialIndex);

if( objectMaterial.reflectionIntensity <= 0.00 )

{

return vec3( 0.0 );

}

Ray reflectionRay;

reflectionRay.direction = normalize( reflect( hitInfo.rayDir, hitInfo.normal ) );

reflectionRay.origin = hitInfo.position + hitInfo.normal * Epsilon;

HitInfo rHitInfo = intersect( reflectionRay );

vec3 color = getObjectsBaseColor(rHitInfo) * objectMaterial.reflectionIntensity;

return color;

}

//--------------------------------------------------------------------------------------------

vec3 calculateRefraction( vec3 viewDir, HitInfo hitInfo )

{

Material objectMaterial = getMaterial(hitInfo.materialIndex);

if( objectMaterial.refractionIntensity <= 0.00 )

{

return vec3( 0.0 );

}

Ray refractionRay;

refractionRay.direction = normalize( refract( hitInfo.rayDir, hitInfo.normal, objectMaterial.refractionIndex ) );

refractionRay.origin = hitInfo.position - hitInfo.normal * Epsilon;

HitInfo rHitInfo = intersect( refractionRay );

for( int i = 0; i < 10; ++i )

{

if( rHitInfo.id == hitInfo.id )

{

refractionRay.origin = rHitInfo.position - rHitInfo.normal * Epsilon;

rHitInfo = intersect( refractionRay );

}

else

{

break;

}

vec3 color = getObjectsBaseColor(rHitInfo) * objectMaterial.refractionIntensity;

return color;

}

//--------------------------------------------------------------------------------------------

float calculateShadow( vec3 lightDir, HitInfo hitInfo )

{

Ray shadowRay;

shadowRay.direction = normalize( lightDir );

shadowRay.origin = hitInfo.position + (shadowRay.direction * 0.001);

HitInfo shadowHitInfo = intersect( shadowRay );

Material mat = getMaterial(shadowHitInfo.materialIndex);

return clamp( mat.shadowCasterIntensity, 0.00, 1.0 );

}

//--------------------------------------------------------------------------------------------

void main(void)

{

float mx = (mouse.x * 2.0 - 1.0) * (ResolutionValue.x / ResolutionValue.y);

float my = (mouse.y * 2.0 - 1.0);

vec2 mouseOffset = vec2( mx, my );

vec2 uv = gl_FragCoord.xy / ResolutionValue.x;

vec2 uvp = (uv * 2.0 - 1.0) + mouseOffset;

Ray ray;

ray.origin = vec3( 0.0, 5.0, 10.0 );

ray.direction = normalize( vec3( uvp, -1.0 ) );

initializeMaterials();

initializeScene();

onAnimateScene();

HitInfo hitInfo = intersect( ray );

vec3 c = vec3( 0.9 );

if( hitInfo.primitiveType <= PrimitiveType_None )

{

gl_FragColor = vec4( c, 1.0 );

return;

}

vec3 lightDir = normalize( lightPos - hitInfo.position );

float shadowFactor = calculateShadow( lightDir, hitInfo );

// Calculate Lighting

Material mat = getMaterial( hitInfo.materialIndex );

float diffuseFactor = clamp( dot( hitInfo.normal, lightDir ), 0.00, 1.00 );

vec3 reflectionVector = normalize( reflect( lightDir, hitInfo.normal ) );

vec3 cameraToSurface = ray.direction;

float specularFactor = pow( clamp( dot( reflectionVector, cameraToSurface ), 0.00, 1.0 ), mat.specularIntensity );

vec3 baseColor = getObjectsBaseColor(hitInfo);

vec3 reflection = calculateReflection( ray.direction, hitInfo );

vec3 refraction = calculateRefraction( ray.direction, hitInfo );

vec3 diffuse = (baseColor + reflection + refraction) * diffuseFactor;

vec3 specular = (mat.specularColor * specularFactor) * step( 1.0, shadowFactor );

c = (diffuse + specular) * shadowFactor;

gl_FragColor = vec4( c, 1.0 );

}

xdPixel

Category Archives: Ray Tracing

GPU Ray Tracer

Practical Computer Graphics