static void Raytracing(Texture2D texture)
{
// View and projection matrices
float4x4 viewMatrix = Transforms.LookAtLH(CameraPosition, float3(0, 1, 0), float3(0, 1, 0));
float4x4 projectionMatrix = Transforms.PerspectiveFovLH(pi_over_4, texture.Height / (float)texture.Width, 0.01f, 20);
Scene <PositionNormalCoordinate, Material> scene = new Scene <PositionNormalCoordinate, Material>();
//CreateMeshScene(scene);
CreateRaycastScene(scene);
// Raycaster to trace rays and check for shadow rays.
Raytracer <ShadowRayPayload, PositionNormalCoordinate, Material> shadower = new Raytracer <ShadowRayPayload, PositionNormalCoordinate, Material>();
shadower.OnAnyHit += delegate(IRaycastContext context, PositionNormalCoordinate attribute, Material material, ref ShadowRayPayload payload)
{
if (any(material.Emissive))
{
return(HitResult.Discard); // Discard light sources during shadow test.
}
// If any object is found in ray-path to the light, the ray is shadowed.
payload.Shadowed = true;
// No neccessary to continue checking other objects
return(HitResult.Stop);
};
// Raycaster to trace rays and lit closest surfaces
Raytracer <MyRayPayload, PositionNormalCoordinate, Material> raycaster = new Raytracer <MyRayPayload, PositionNormalCoordinate, Material>();
raycaster.OnClosestHit += delegate(IRaycastContext context, PositionNormalCoordinate attribute, Material material, ref MyRayPayload payload)
{
// Move geometry attribute to world space
attribute = attribute.Transform(context.FromGeometryToWorld);
float3 V = -normalize(context.GlobalRay.Direction);
float3 L = (LightPosition - attribute.Position);
float d = length(L);
L /= d; // normalize direction to light reusing distance to light
attribute.Normal = normalize(attribute.Normal);
if (material.BumpMap != null)
{
float3 T, B;
createOrthoBasis(attribute.Normal, out T, out B);
float3 tangentBump = material.BumpMap.Sample(material.TextureSampler, attribute.Coordinates).xyz * 2 - 1;
float3 globalBump = tangentBump.x * T + tangentBump.y * B + tangentBump.z * attribute.Normal;
//attribute.Normal = globalBump;
attribute.Normal = normalize(attribute.Normal + globalBump);
}
float lambertFactor = max(0, dot(attribute.Normal, L));
// Check ray to light...
ShadowRayPayload shadow = new ShadowRayPayload();
shadower.Trace(scene,
RayDescription.FromDir(attribute.Position + attribute.Normal * 0.001f, // Move an epsilon away from the surface to avoid self-shadowing
L), ref shadow);
float3 Intensity = (shadow.Shadowed ? 0.2f : 1.0f) * LightIntensity / (d * d);
payload.Color = material.Emissive + material.EvalBRDF(attribute, V, L) * Intensity * lambertFactor; // direct light computation
// Recursive calls for indirect light due to reflections and refractions
if (payload.Bounces > 0)
{
foreach (var impulse in material.GetBRDFImpulses(attribute, V))
{
float3 D = impulse.Direction; // recursive direction to check
float3 facedNormal = dot(D, attribute.Normal) > 0 ? attribute.Normal : -attribute.Normal; // normal respect to direction
RayDescription ray = new RayDescription {
Direction = D, Origin = attribute.Position + facedNormal * 0.001f, MinT = 0.0001f, MaxT = 10000
};
MyRayPayload newPayload = new MyRayPayload
{
Bounces = payload.Bounces - 1
};
raycaster.Trace(scene, ray, ref newPayload);
payload.Color += newPayload.Color * impulse.Ratio;
}
}
};
raycaster.OnMiss += delegate(IRaycastContext context, ref MyRayPayload payload)
{
payload.Color = float3(0, 0, 0); // Blue, as the sky.
};
/// Render all points of the screen
for (int px = 0; px < texture.Width; px++)
{
for (int py = 0; py < texture.Height; py++)
{
int progress = (px * texture.Height + py);
if (progress % 1000 == 0)
{
Console.Write("\r" + progress * 100 / (float)(texture.Width * texture.Height) + "% ");
}
RayDescription ray = RayDescription.FromScreen(px + 0.5f, py + 0.5f, texture.Width, texture.Height, inverse(viewMatrix), inverse(projectionMatrix), 0, 1000);
MyRayPayload coloring = new MyRayPayload();
coloring.Bounces = 3;
raycaster.Trace(scene, ray, ref coloring);
texture.Write(px, py, float4(coloring.Color, 1));
}
}
}
static void RaycastingMeshTexture(Texture2D texture, Material mat)
{
// Scene Setup
float3 CameraPosition = float3(3, 2f, 4);
float3 LightPosition = float3(3, 5, -2);
float3 LightIntensity = float3(1, 1, 1) * 100;
// View and projection matrices
float4x4 viewMatrix = Transforms.LookAtLH(CameraPosition, float3(0, 1, 0), float3(0, 1, 0));
float4x4 projectionMatrix = Transforms.PerspectiveFovLH(pi_over_4, texture.Height / (float)texture.Width, 0.01f, 20);
Scene <PositionNormalCoordinate, Material> scene = new Scene <PositionNormalCoordinate, Material>();
CreateMeshScene(scene);
//CreateRaycastScene(scene, mat);
// Raycaster to trace rays and check for shadow rays.
Raytracer <ShadowRayPayload, PositionNormalCoordinate, Material> shadower = new Raytracer <ShadowRayPayload, PositionNormalCoordinate, Material>();
shadower.OnAnyHit += delegate(IRaycastContext context, PositionNormalCoordinate attribute, Material material, ref ShadowRayPayload payload)
{
// If any object is found in ray-path to the light, the ray is shadowed.
payload.Shadowed = true;
// No neccessary to continue checking other objects
return(HitResult.Stop);
};
// Raycaster to trace rays and lit closest surfaces
Raytracer <MyRayPayload, PositionNormalCoordinate, Material> raycaster = new Raytracer <MyRayPayload, PositionNormalCoordinate, Material>();
raycaster.OnClosestHit += delegate(IRaycastContext context, PositionNormalCoordinate attribute, Material material, ref MyRayPayload payload)
{
// Move geometry attribute to world space
attribute = attribute.Transform(context.FromGeometryToWorld);
float3 V = normalize(CameraPosition - attribute.Position);
float3 L = (LightPosition - attribute.Position);
float d = length(L);
L /= d; // normalize direction to light reusing distance to light
attribute.Normal = normalize(attribute.Normal);
float lambertFactor = max(0, dot(attribute.Normal, L));
// Check ray to light...
ShadowRayPayload shadow = new ShadowRayPayload();
shadower.Trace(scene,
RayDescription.FromDir(attribute.Position + attribute.Normal * 0.001f, // Move an epsilon away from the surface to avoid self-shadowing
L), ref shadow);
float3 Intensity = (shadow.Shadowed ? 0.2f : 1.0f) * LightIntensity / (d * d);
payload.Color = material.EvalBRDF(attribute, V, L) * Intensity * lambertFactor;
};
raycaster.OnMiss += delegate(IRaycastContext context, ref MyRayPayload payload)
{
payload.Color = float3(0, 0, 0); // Blue, as the sky.
};
/// Render all points of the screen
for (int px = 0; px < texture.Width; px++)
{
for (int py = 0; py < texture.Height; py++)
{
int progress = (px * texture.Height + py);
if (progress % 1000 == 0)
{
Console.Write("\r" + progress * 100 / (float)(texture.Width * texture.Height) + "% ");
}
RayDescription ray = RayDescription.FromScreen(px + 0.5f, py + 0.5f, texture.Width, texture.Height, inverse(viewMatrix), inverse(projectionMatrix), 0, 1000);
MyRayPayload coloring = new MyRayPayload();
raycaster.Trace(scene, ray, ref coloring);
texture.Write(px, py, float4(coloring.Color, 1));
}
}
}