mirror of
https://github.com/Mercury-Language/mercury.git
synced 2026-04-18 02:43:40 +00:00
a94cacec1a
Estimated hours taken: 1 Add and enable a regression test case to make sure value numbering can handle floating point numbers. The code is an extract from Tom's scene.m.
136 lines
3.6 KiB
Mathematica
136 lines
3.6 KiB
Mathematica
% This is a regression test. Some versions of the compiler reported
|
|
% an internal error when compiling with value numbering.
|
|
|
|
% This code comes from Tom Conway's ray tracer.
|
|
|
|
:- module vn_float.
|
|
|
|
:- interface.
|
|
|
|
:- import_module list, array.
|
|
|
|
:- type vec3 ---> vec(float, float, float).
|
|
|
|
:- pred get_planar_coords(list(int), array(vec3), list(vec3), vec3).
|
|
:- mode get_planar_coords(in, in, out, out) is det.
|
|
|
|
:- implementation.
|
|
|
|
:- import_module require, math, float, int, std_util.
|
|
|
|
:- type mat3 ---> mat(vec3, vec3, vec3).
|
|
|
|
get_planar_coords(IndList, VertArr, PlaneList, Norm) :-
|
|
(
|
|
IndList = [Ind1, Ind2, Ind3 | _IndList1]
|
|
->
|
|
% lookup first 3 vertices and calculate normal
|
|
array__lookup(VertArr, Ind1+1, V1),
|
|
array__lookup(VertArr, Ind2+1, V2),
|
|
array__lookup(VertArr, Ind3+1, V3),
|
|
Norm = unit(cross(V3 - V2, V1 - V2)),
|
|
get_angles_from_z_axis(Norm, Theta, Phi),
|
|
|
|
% need to rotate -Theta about Z axis then -Phi about Y axis
|
|
math__cos(-Theta, CosZ),
|
|
math__sin(-Theta, SinZ),
|
|
math__cos(-Phi, CosY),
|
|
math__sin(-Phi, SinY),
|
|
MZ = mat(vec(CosZ,-SinZ,0.0), vec(SinZ,CosZ,0.0), vec(0.0,0.0,1.0)),
|
|
MY = mat(vec(CosY,0.0,SinY), vec(0.0,1.0,0.0), vec(-SinY,0.0,CosY)),
|
|
M = matmult(MZ, MY),
|
|
move_vertices_to_plane(IndList, VertArr, -V1, M, PlaneList)
|
|
;
|
|
error("Something strange has happend to the vertex list")
|
|
).
|
|
|
|
:- pred get_angles_from_z_axis(vec3, float, float).
|
|
:- mode get_angles_from_z_axis(in, out, out) is det.
|
|
|
|
get_angles_from_z_axis(Vec, Theta, Phi) :-
|
|
(
|
|
Vec = vec(X, Y, Z),
|
|
Vector_radius = mag(Vec),
|
|
XY_radius = mag(vec(X, Y, 0.0)), % magnitude of xy projection
|
|
math__pi(Pi), % get a useful constant
|
|
(
|
|
Vector_radius = 0.0
|
|
->
|
|
error("get_angles_from_z_axis: vector should not be zero-length")
|
|
;
|
|
% check if vector is already on z axis
|
|
(
|
|
XY_radius = 0.0
|
|
->
|
|
Theta = 0.0,
|
|
Phi = 0.0
|
|
;
|
|
float__abs(X, Xabs),
|
|
math__asin(Xabs / XY_radius, Theta1),
|
|
math__asin(XY_radius / Vector_radius, Phi1),
|
|
|
|
% angles have been calculated for the first octant
|
|
% they need to be corrected for the octant they are actually in
|
|
(
|
|
X =< 0.0
|
|
->
|
|
(
|
|
Y =< 0.0
|
|
->
|
|
Theta = Pi + Theta1
|
|
;
|
|
Theta = Pi - Theta1
|
|
)
|
|
;
|
|
(
|
|
Y =< 0.0
|
|
->
|
|
Theta = -Theta1
|
|
;
|
|
Theta = Theta1
|
|
)
|
|
),
|
|
(
|
|
Z =< 0.0
|
|
->
|
|
Phi = Phi1 + Pi / 2.0
|
|
;
|
|
Phi = Phi1
|
|
)
|
|
)
|
|
)
|
|
).
|
|
|
|
:- pred move_vertices_to_plane(list(int), array(vec3), vec3, mat3, list(vec3)).
|
|
:- mode move_vertices_to_plane(in, in, in, in, out) is det.
|
|
|
|
:- external(move_vertices_to_plane/5).
|
|
|
|
:- func unit(vec3) = vec3.
|
|
|
|
:- external(unit/1).
|
|
|
|
:- func cross(vec3, vec3) = vec3.
|
|
|
|
:- external(cross/2).
|
|
|
|
:- func '-'(vec3, vec3) = vec3.
|
|
|
|
:- external(('-')/2).
|
|
|
|
:- func '-'(vec3) = vec3.
|
|
|
|
:- external(('-')/1).
|
|
|
|
:- func mag(vec3) = float.
|
|
|
|
:- external(mag/1).
|
|
|
|
:- func '*'(vec3, mat3) = vec3.
|
|
|
|
:- external('*'/2).
|
|
|
|
:- func matmult(mat3, mat3) = mat3.
|
|
|
|
:- external(matmult/2).
|