Data.Glome.Solid

Documentation

data Rayint tag mat

Ray intersection type. If we hit, we store the distance from the ray origin, the position, the normal, the transformed ray, UV coordinates (plus a 3rd coordinate we'll call W) and the texture and tag stacks attached to the object.

Constructors

RayHit

Fields

ridepth' :: !Flt

ripos :: !Vec

rinorm :: !Vec

riray :: !Ray

riuvw :: !Vec

ritex :: [Texture tag mat]

ritag :: [tag]

RayMiss

Instances

Read (Texture () (Material ()))

Show (Texture t m)

This is sort of a no-op; textures are functions, and we don't have a good way to show an arbitrary function

Show tag => Show (Rayint tag mat)

raymiss :: Rayint tag mat

ridepth :: Rayint tag mat -> Flt

nearest :: Rayint tag mat -> Rayint tag mat -> Rayint tag mat

Pick the closest of two Rayints

furthest :: Rayint tag mat -> Rayint tag mat -> Rayint tag mat

Pick the furthest of two Rayints

hit :: Rayint tag mat -> Bool

Test if a Rayint is a hit or a miss

dist :: Rayint tag mat -> Flt

Extract a distance from a Rayint, with infinity for a miss

data PacketResult tag mat

Sometimes, it's more efficient to trace multiple rays against an acceleration structure at the same time, provided the rays are almost identical. A PacketResult is the result of tracing 4 rays at once.

Constructors

PacketResult (Rayint tag mat) (Rayint tag mat) (Rayint tag mat) (Rayint tag mat)

packetmiss :: PacketResult tag mat

nearest_packetresult :: PacketResult tag mat -> PacketResult tag mat -> PacketResult tag mat

rayint_advance :: SolidItem tag mat -> Ray -> Flt -> [Texture tag mat] -> [tag] -> Flt -> Rayint tag mat

Move a ray forward and test the new ray against an object. Fix the depth of the result. Useful in CSG

type Texture tag mat = Ray -> Rayint tag mat -> mat

A texture is a function that takes a Rayint and returns a material. A material will later be rendered by a shader (which in turn can append more tags).

newtype Pcount

Constructors

Pcount (Int, Int, Int)

Instances

Show Pcount

pcadd :: Pcount -> Pcount -> Pcount

asbound :: Pcount -> Pcount

pcsinglexfm :: Pcount

pcsingleprim :: Pcount

pcsinglebound :: Pcount

pcnone :: Pcount

debug_wrap :: (Rayint tag mat, Int) -> Int -> (Rayint tag mat, Int)

nearest_debug :: (Rayint tag mat, Int) -> (Rayint tag mat, Int) -> (Rayint tag mat, Int)

class Show s => Solid s t m | s -> t, s -> m where

A solid is something we can test a ray against or do inside/outside tests. Some of these are simple solids like Sphere or Triangle, but others are composite solids than have other solids as children.

Methods

rayint

Arguments

:: s

object to test against

-> Ray

ray

-> Flt

maximum distance we care about

-> [Texture t m]

current texture stack (Tex object pushes new textures)

-> [t]

tag stack (Tag object pushes new tags)

-> Rayint t m

we return a Rayint describing the hit location

Test a ray against a solid, returning a ray intersection. The distance parameter is used to specify a max distance. If it's further away, we aren't interested in the intersection. The b parameter is a default tag, if it's not overridden by a more specific tag (which is useful if we need to be able to identify the thing that was hit).

rayint_debug :: s -> Ray -> Flt -> [Texture t m] -> [t] -> (Rayint t m, Int)

Same as rayint, but return a count of the number of primitives checked. Useful for optimizing acceleration structures.

packetint :: s -> Ray -> Ray -> Ray -> Ray -> Flt -> [Texture t m] -> [t] -> PacketResult t m

Trace four rays at once against a solid.

shadow :: s -> Ray -> Flt -> Bool

Shadow test - we just return a Bool rather than return a a full Rayint.

inside :: s -> Vec -> Bool

Test if a point is inside an object. Useful for CSG. Objects with no volume just return False.

bound :: s -> Bbox

Generate an axis-aligned bounding box than completely encloses the object. For performance, it is important that this fits as tight as possible.

tolist :: s -> [SolidItem t m]

Most simple objects just return themselves as a singleton list, but for composite objects, we flatten the structure out and return a list. We usually do this prior to re-building a composite object in a (hopefully) more efficient fashion.

transform :: s -> [Xfm] -> SolidItem t m

Create a new object transformed by some transformation. The reason this method exists is so we can override it for the Instance type - if we transform a transformation, we should combine the two matricies into one. Most objects can use the default implementation.

transform_leaf :: s -> [Xfm] -> SolidItem t m

Used by flatten_transform. I don't really remember how it works.

flatten_transform :: s -> [SolidItem t m]

Take a composite object inside a transform, and turn it into a group of individually-transformed objects. Most objects can use the defaut implementation.

primcount :: s -> Pcount

Count the number of primitives, transforms, and bounding objects in a scene. Simple objects can just use the default, which is to return a single primitive.

get_metainfo :: s -> Vec -> ([Texture t m], [t])

Get texture and tag data for a primitive, from a point.

Instances

Solid [SolidItem t m] t m

Solid (Instance t m) t m

Solid (Void t m) t m

Solid (SolidItem t m) t m

data SolidItem t m

We create an existential type for solids so we can emded them in composite types without know what kind of solid it is. http:notes-on-haskell.blogspot.com200701/proxies-and-delegation-vs-existential.html

Constructors

forall s . Solid s t m => SolidItem s

Instances

Read SI

Read [SI]

Solid [SolidItem t m] t m

Show (SolidItem t m)

Solid (SolidItem t m) t m

group :: [SolidItem t m] -> SolidItem t m

A group is just a list of objects. Sometimes its convenient to be able to treat a group as if it were a single object, and that is exactly what we do here. The ray intersection routine tests the ray against each object in turn. Not very efficient for large groups, but this is a useful building block for constructing the leaves of acceleration structures. (See the bih module.)

flatten_group :: [SolidItem t m] -> [SolidItem t m]

Smash a group of groups into a single group, so we can build an efficient bounding heirarchy

paircat :: ([a], [b]) -> ([a], [b]) -> ([a], [b])

data Void t m

A Void is a non-object, that we treat as if it were one. This is functionally equivalent to an empty Group. (Originally I called this Nothing, but that conflicted with the prelude maybe type, so I call it Void instead)

Constructors

Void

Instances

Show (Void t m)

Solid (Void t m) t m

nothing :: SolidItem t m

data Instance t m

An instance is a primitive that has been modified by a transformation (i.e. some combination of translation, rotation, and scaling). This is a reasonably space-efficient way of making multiple copies of a complex object.

Usually, the application doesn't need to create an instance directly, but should use transform on an existing object.

It's unfortunate that instance is also a reserved word. instance Solid Instance where... is a little confusing.

This would be better in its own module, but we need Instance to be defined here so we can define the default implementation of transform in terms on Instance. (Mutually recursive modules would be useful, if I could get them to work.)

Another good reason to include Instance in Solid.hs is that it's referenced from Cone.hs

Constructors

Instance (SolidItem t m) Xfm

Instances

Show (Instance t m)

Solid (Instance t m) t m

rayint_instance :: Instance tag mat -> Ray -> Flt -> [Texture tag mat] -> [tag] -> Rayint tag mat

packetint_instance :: Instance tag mat -> Ray -> Ray -> Ray -> Ray -> Flt -> [Texture tag mat] -> [tag] -> PacketResult tag mat

rayint_debug_instance :: Instance tag mat -> Ray -> Flt -> [Texture tag mat] -> [tag] -> (Rayint tag mat, Int)

shadow_instance :: Instance tag mat -> Ray -> Flt -> Bool

inside_instance :: Instance tag mat -> Vec -> Bool

bound_instance :: Instance tag mat -> Bbox

transform_instance :: Instance tag mat -> [Xfm] -> SolidItem tag mat

transform_leaf_instance :: Instance tag mat -> [Xfm] -> SolidItem tag mat

flatten_transform_instance :: Instance tag mat -> [SolidItem tag mat]

primcount_instance :: Instance tag mat -> Pcount

get_metainfo_instance :: Instance tag mat -> Vec -> ([Texture tag mat], [tag])