ref: d4c1f40bd25a2241d47ff5cfaa8b0e2a3906b265
dir: /auxiliary/hat-test.c/
/*
* Standalone test program for hat.c, which generates patches of hat
* tiling in multiple output formats without also generating a Loopy
* puzzle around them.
*/
#include <assert.h>
#ifdef NO_TGMATH_H
# include <math.h>
#else
# include <tgmath.h>
#endif
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include "hat-internal.h"
static HatCoords *hat_coords_construct_v(TileType type, va_list ap)
{
HatCoords *hc = hat_coords_new();
while (true) {
int index = va_arg(ap, int);
hat_coords_make_space(hc, hc->nc + 1);
hc->c[hc->nc].type = type;
hc->c[hc->nc].index = index;
hc->nc++;
if (index < 0)
return hc;
type = va_arg(ap, TileType);
}
}
static HatCoords *hat_coords_construct(TileType type, ...)
{
HatCoords *hc;
va_list ap;
va_start(ap, type);
hc = hat_coords_construct_v(type, ap);
va_end(ap);
return hc;
}
static bool hat_coords_equal(HatCoords *hc1, HatCoords *hc2)
{
size_t i;
if (hc1->nc != hc2->nc)
return false;
for (i = 0; i < hc1->nc; i++) {
if (hc1->c[i].type != hc2->c[i].type ||
hc1->c[i].index != hc2->c[i].index)
return false;
}
return true;
}
static bool hat_coords_expect(const char *file, int line, HatCoords *hc,
TileType type, ...)
{
bool equal;
va_list ap;
HatCoords *hce;
va_start(ap, type);
hce = hat_coords_construct_v(type, ap);
va_end(ap);
equal = hat_coords_equal(hc, hce);
if (!equal) {
fprintf(stderr, "%s:%d: coordinate mismatch\n", file, line);
hat_coords_debug(" expected: ", hce, "\n");
hat_coords_debug(" actual: ", hc, "\n");
}
hat_coords_free(hce);
return equal;
}
#define EXPECT(hc, ...) do { \
if (!hat_coords_expect(__FILE__, __LINE__, hc, __VA_ARGS__)) \
fails++; \
} while (0)
/*
* For four-colouring the tiling: these tables give a colouring of
* each kitemap, with colour 3 assigned to the reflected tiles in the
* middle of the H, and 0,1,2 chosen arbitrarily.
*/
static const int fourcolours_H[] = {
/* 0 */ 0, 2, 1, 3,
/* 1 */ 1, 0, 2, 3,
/* 2 */ 0, 2, 1, 3,
/* 3 */ 1, -1, -1, -1,
/* 4 */ 1, 2, -1, -1,
/* 5 */ 1, 2, -1, -1,
/* 6 */ 2, 1, -1, -1,
/* 7 */ 0, 1, -1, -1,
/* 8 */ 2, 0, -1, -1,
/* 9 */ 2, 0, -1, -1,
/* 10 */ 0, 1, -1, -1,
/* 11 */ 0, 1, -1, -1,
/* 12 */ 2, 0, -1, -1,
};
static const int fourcolours_T[] = {
/* 0 */ 1, 2, 0, 3,
/* 1 */ 2, 1, -1, -1,
/* 2 */ 0, 1, -1, -1,
/* 3 */ 0, 2, -1, -1,
/* 4 */ 2, 0, -1, -1,
/* 5 */ 0, 1, -1, -1,
/* 6 */ 1, 2, -1, -1,
};
static const int fourcolours_P[] = {
/* 0 */ 2, 1, 0, 3,
/* 1 */ 1, 2, 0, 3,
/* 2 */ 2, 1, -1, -1,
/* 3 */ 0, 2, -1, -1,
/* 4 */ 0, 1, -1, -1,
/* 5 */ 1, 2, -1, -1,
/* 6 */ 2, 0, -1, -1,
/* 7 */ 0, 1, -1, -1,
/* 8 */ 1, 0, -1, -1,
/* 9 */ 2, 1, -1, -1,
/* 10 */ 0, 2, -1, -1,
};
static const int fourcolours_F[] = {
/* 0 */ 2, 0, 1, 3,
/* 1 */ 0, 2, 1, 3,
/* 2 */ 1, 2, -1, -1,
/* 3 */ 1, 0, -1, -1,
/* 4 */ 0, 2, -1, -1,
/* 5 */ 2, 1, -1, -1,
/* 6 */ 2, 0, -1, -1,
/* 7 */ 0, 1, -1, -1,
/* 8 */ 0, 1, -1, -1,
/* 9 */ 2, 0, -1, -1,
/* 10 */ 1, 2, -1, -1,
};
static const int *const fourcolours[] = {
fourcolours_H, fourcolours_T, fourcolours_P, fourcolours_F,
};
static bool unit_tests(void)
{
int fails = 0;
HatContext ctx[1];
HatCoords *hc_in, *hc_out;
ctx->rs = NULL;
ctx->prototype = hat_coords_construct(TT_KITE, 0, TT_HAT, 0, TT_H, -1);
/* Simple steps within a hat */
hc_in = hat_coords_construct(TT_KITE, 6, TT_HAT, 2, TT_H, 1, TT_H, -1);
hc_out = hatctx_step(ctx, hc_in, KS_LEFT);
EXPECT(hc_out, TT_KITE, 5, TT_HAT, 2, TT_H, 1, TT_H, -1);
hat_coords_free(hc_in);
hat_coords_free(hc_out);
hc_in = hat_coords_construct(TT_KITE, 6, TT_HAT, 2, TT_H, 1, TT_H, -1);
hc_out = hatctx_step(ctx, hc_in, KS_RIGHT);
EXPECT(hc_out, TT_KITE, 7, TT_HAT, 2, TT_H, 1, TT_H, -1);
hat_coords_free(hc_in);
hat_coords_free(hc_out);
hc_in = hat_coords_construct(TT_KITE, 5, TT_HAT, 2, TT_H, 1, TT_H, -1);
hc_out = hatctx_step(ctx, hc_in, KS_F_LEFT);
EXPECT(hc_out, TT_KITE, 2, TT_HAT, 2, TT_H, 1, TT_H, -1);
hat_coords_free(hc_in);
hat_coords_free(hc_out);
hc_in = hat_coords_construct(TT_KITE, 5, TT_HAT, 2, TT_H, 1, TT_H, -1);
hc_out = hatctx_step(ctx, hc_in, KS_F_RIGHT);
EXPECT(hc_out, TT_KITE, 1, TT_HAT, 2, TT_H, 1, TT_H, -1);
hat_coords_free(hc_in);
hat_coords_free(hc_out);
/* Step between hats in the same kitemap, which can change the
* metatile type at layer 2 */
hc_in = hat_coords_construct(TT_KITE, 6, TT_HAT, 2, TT_H, 1, TT_H, -1);
hc_out = hatctx_step(ctx, hc_in, KS_F_LEFT);
EXPECT(hc_out, TT_KITE, 3, TT_HAT, 0, TT_H, 0, TT_H, -1);
hat_coords_free(hc_in);
hat_coords_free(hc_out);
hc_in = hat_coords_construct(TT_KITE, 7, TT_HAT, 2, TT_H, 1, TT_H, -1);
hc_out = hatctx_step(ctx, hc_in, KS_F_RIGHT);
EXPECT(hc_out, TT_KITE, 4, TT_HAT, 0, TT_T, 3, TT_H, -1);
hat_coords_free(hc_in);
hat_coords_free(hc_out);
/* Step off the edge of one kitemap, necessitating a metamap
* rewrite of layers 2,3 to get into a different kitemap where
* that step can be made */
hc_in = hat_coords_construct(TT_KITE, 6, TT_HAT, 0, TT_P, 2, TT_P, 3,
TT_P, -1);
hc_out = hatctx_step(ctx, hc_in, KS_F_RIGHT);
/* Working:
* kite 6 . hat 0 . P 2 . P 3 . P ?
* -> kite 6 . hat 0 . P 6 . H 0 . P ? (P metamap says 2.3 = 6.0)
*/
EXPECT(hc_out, TT_KITE, 7, TT_HAT, 1, TT_H, 1, TT_H, 0, TT_P, -1);
hat_coords_free(hc_in);
hat_coords_free(hc_out);
hatctx_cleanup(ctx);
return fails == 0;
}
/*
* Structure that describes how the colours in the above maps are
* translated to output colours. This will vary with each kitemap our
* coordinates pass through, in order to maintain consistency.
*/
typedef struct FourColourMap {
unsigned char map[4];
} FourColourMap;
/*
* Make an initial FourColourMap by choosing the initial permutation
* of the three 'normal' hat colours randomly.
*/
static inline FourColourMap fourcolourmap_initial(random_state *rs)
{
FourColourMap f;
unsigned i;
/* Start with the identity mapping */
for (i = 0; i < 4; i++)
f.map[i] = i;
/* Randomly permute colours 0,1,2, leaving 3 as the distinguished
* colour for reflected hats */
shuffle(f.map, 3, sizeof(f.map[0]), rs);
return f;
}
static inline FourColourMap fourcolourmap_update(
FourColourMap prevm, HatCoords *prevc, HatCoords *currc, KiteStep step,
HatContext *ctx)
{
size_t i, m1, m2;
const int *f1, *f2;
unsigned sum;
int missing;
FourColourMap newm;
HatCoords *prev2c;
/*
* If prevc and currc are in the same kitemap anyway, that's the
* easy case: the colour map for the new kitemap is the same as
* for the old one, because they're the same kitemap.
*/
hatctx_extend_coords(ctx, prevc, currc->nc);
hatctx_extend_coords(ctx, currc, prevc->nc);
for (i = 3; i < prevc->nc; i++)
if (currc->c[i].index != prevc->c[i].index)
goto mismatch;
return prevm;
mismatch:
/*
* The hatctx_step algorithm guarantees that the _new_ coordinate
* currc is expected to be in a kitemap containing both this kite
* and the previous one (because it first transformed the previous
* coordinate until it _could_ take a step within the same
* kitemap, and then did).
*
* So if we reverse the last step we took, we should get a second
* HatCoords describing the same kite as prevc but showing its
* position in the _new_ kitemap. This lets us figure out a pair
* of corresponding metatile indices within the old and new
* kitemaps (by looking at which metatile prevc and prev2c claim
* to be in).
*
* That metatile will also always be a P or an F (because all
* metatiles overlapping the next kitemap are of those types),
* which means it will have two hats in it. And those hats will be
* adjacent, so differently coloured. Hence, we have enough
* information to decide how two of the new kitemap's three normal
* colours map to the colours we were using in the old kitemap -
* and then the third is determined by process of elimination.
*/
prev2c = hatctx_step(
ctx, currc, (step == KS_LEFT ? KS_RIGHT :
step == KS_RIGHT ? KS_LEFT :
step == KS_F_LEFT ? KS_F_RIGHT : KS_F_LEFT));
/* Metatile indices within the old and new kitemaps */
m1 = prevc->c[2].index;
m2 = prev2c->c[2].index;
/* The colourings of those metatiles' hats in our fixed fourcolours[] */
f1 = fourcolours[prevc->c[3].type] + 4*m1;
f2 = fourcolours[prev2c->c[3].type] + 4*m2;
hat_coords_free(prev2c);
/*
* Start making our new output map, filling in all three normal
* colours to 255 = "don't know yet".
*/
newm.map[3] = 3;
newm.map[0] = newm.map[1] = newm.map[2] = 255;
/*
* Iterate over the tile colourings in fourcolours[] for these
* metatiles, matching up our mappings.
*/
for (i = 0; i < 4; i++) {
/* They should be the same metatile, so have same number of hats! */
if (f1[i] == -1 && f2[i] == -1)
continue;
assert(f1[i] != -1 && f2[i] != -1);
if (f1[i] != 255)
newm.map[f2[i]] = prevm.map[f1[i]];
}
/*
* We expect to have filled in exactly two of the three normal
* colours. Find the missing index, and fill in its colour by
* arithmetic (using the fact that the three colours add up to 3).
*/
sum = 0;
missing = -1;
for (i = 0; i < 3; i++) {
if (newm.map[i] == 255) {
assert(missing == -1); /* shouldn't have two missing colours */
missing = i;
} else {
sum += newm.map[i];
}
}
assert(missing != -1);
assert(0 < sum && sum <= 3);
newm.map[missing] = 3 - sum;
return newm;
}
typedef struct pspoint {
float x, y;
} pspoint;
typedef struct psbbox {
bool started;
pspoint bl, tr;
} psbbox;
static inline void psbbox_add(psbbox *bbox, pspoint p)
{
if (!bbox->started || bbox->bl.x > p.x)
bbox->bl.x = p.x;
if (!bbox->started || bbox->tr.x < p.x)
bbox->tr.x = p.x;
if (!bbox->started || bbox->bl.y > p.y)
bbox->bl.y = p.y;
if (!bbox->started || bbox->tr.y < p.y)
bbox->tr.y = p.y;
bbox->started = true;
}
typedef enum OutFmt { OF_POSTSCRIPT, OF_SVG, OF_PYTHON } OutFmt;
typedef enum ColourMode { CM_SEMANTIC, CM_FOURCOLOUR } ColourMode;
typedef struct drawctx {
OutFmt outfmt;
ColourMode colourmode;
psbbox *bbox;
KiteEnum *kiteenum;
FourColourMap fourcolourmap[KE_NKEEP];
bool natural_scale, clip;
float xoff, xscale, yoff, yscale; /* used for SVG only */
} drawctx;
static void bbox_add_hat(void *vctx, Kite kite0, HatCoords *hc, int *coords)
{
drawctx *ctx = (drawctx *)vctx;
pspoint p;
size_t i;
for (i = 0; i < 14; i++) {
p.x = coords[2*i] * 1.5;
p.y = coords[2*i+1] * sqrt(0.75);
psbbox_add(ctx->bbox, p);
}
}
static void header(drawctx *ctx)
{
float scale, ox, oy;
/* Optionally clip to an inner rectangle that guarantees
* the whole visible area is covered in hats. */
if (ctx->clip) {
ctx->bbox->bl.x += 9;
ctx->bbox->tr.x -= 9;
ctx->bbox->bl.y += 12 * sqrt(0.75);
ctx->bbox->tr.y -= 12 * sqrt(0.75);
}
if (!ctx->natural_scale) {
/* Scale the output to fit on an A4 page, for test prints. */
float w = 595, h = 842, margin = 12;
float xext = ctx->bbox->tr.x - ctx->bbox->bl.x;
float yext = ctx->bbox->tr.y - ctx->bbox->bl.y;
float xscale = (w - 2*margin) / xext;
float yscale = (h - 2*margin) / yext;
scale = xscale < yscale ? xscale : yscale;
ox = (w - scale * (ctx->bbox->bl.x + ctx->bbox->tr.x)) / 2;
oy = (h - scale * (ctx->bbox->bl.y + ctx->bbox->tr.y)) / 2;
} else {
/* Leave the patch at its natural scale. */
scale = 1.0;
/* And translate the lower left corner of the bounding box to 0. */
ox = -ctx->bbox->bl.x;
oy = -ctx->bbox->bl.y;
}
switch (ctx->outfmt) {
case OF_POSTSCRIPT: {
printf("%%!PS-Adobe-2.0\n%%%%Creator: hat-test from Simon Tatham's "
"Portable Puzzle Collection\n%%%%Pages: 1\n"
"%%%%BoundingBox: %f %f %f %f\n"
"%%%%EndComments\n%%%%Page: 1 1\n",
ox + scale * ctx->bbox->bl.x,
oy + scale * ctx->bbox->bl.y,
ox + scale * ctx->bbox->tr.x,
oy + scale * ctx->bbox->tr.y);
if (ctx->clip) {
printf("%f %f moveto %f %f lineto %f %f lineto %f %f lineto "
"closepath clip\n",
ox + scale * ctx->bbox->bl.x,
oy + scale * ctx->bbox->bl.y,
ox + scale * ctx->bbox->bl.x,
oy + scale * ctx->bbox->tr.y,
ox + scale * ctx->bbox->tr.x,
oy + scale * ctx->bbox->tr.y,
ox + scale * ctx->bbox->tr.x,
oy + scale * ctx->bbox->bl.y);
}
printf("%f %f translate %f dup scale\n", ox, oy, scale);
printf("%f setlinewidth\n", 0.06);
printf("0 setgray 1 setlinejoin 1 setlinecap\n");
break;
}
case OF_SVG: {
printf("<?xml version=\"1.0\" encoding=\"UTF-8\" "
"standalone=\"no\"?>\n");
printf("<svg xmlns=\"http://www.w3.org/2000/svg\" "
"version=\"1.1\" width=\"%f\" height=\"%f\">\n",
scale * (ctx->bbox->tr.x - ctx->bbox->bl.x),
scale * (ctx->bbox->tr.y - ctx->bbox->bl.y));
printf("<style type=\"text/css\">\n");
printf("path { fill: none; stroke: black; stroke-width: %f; "
"stroke-linejoin: round; stroke-linecap: round; }\n",
0.06 * scale);
switch (ctx->colourmode) {
case CM_SEMANTIC:
printf(".H { fill: rgb(153, 204, 255); }\n");
printf(".H3 { fill: rgb( 0, 128, 204); }\n");
printf(".T, .P { fill: rgb(255, 255, 255); }\n");
printf(".F { fill: rgb(178, 178, 178); }\n");
break;
default /* case CM_FOURCOLOUR */:
printf(".c0 { fill: rgb(255, 178, 178); }\n");
printf(".c1 { fill: rgb(255, 255, 178); }\n");
printf(".c2 { fill: rgb(178, 255, 178); }\n");
printf(".c3 { fill: rgb(153, 153, 255); }\n");
break;
}
printf("</style>\n");
ctx->xoff = -ctx->bbox->bl.x * scale;
ctx->xscale = scale;
ctx->yoff = ctx->bbox->tr.y * scale;
ctx->yscale = -scale;
break;
}
default:
break;
}
}
static void draw_hat(void *vctx, Kite kite0, HatCoords *hc, int *coords)
{
drawctx *ctx = (drawctx *)vctx;
pspoint p;
size_t i;
int orientation;
/*
* Determine an index for the hat's orientation, based on the axis
* of symmetry of its kite #0.
*/
{
int dx = kite0.outer.x - kite0.centre.x;
int dy = kite0.outer.y - kite0.centre.y;
orientation = 0;
while (dx < 0 || dy < 0) {
int newdx = dx + dy;
int newdy = -dx;
dx = newdx;
dy = newdy;
orientation++;
assert(orientation < 6);
}
}
switch (ctx->outfmt) {
case OF_POSTSCRIPT: {
const char *colour;
printf("newpath");
for (i = 0; i < 14; i++) {
p.x = coords[2*i] * 1.5;
p.y = coords[2*i+1] * sqrt(0.75);
printf(" %f %f %s", p.x, p.y, i ? "lineto" : "moveto");
}
printf(" closepath gsave");
switch (ctx->colourmode) {
case CM_SEMANTIC:
if (hc->c[2].type == TT_H) {
colour = (hc->c[1].index == 3 ? "0 0.5 0.8 setrgbcolor" :
"0.6 0.8 1 setrgbcolor");
} else if (hc->c[2].type == TT_F) {
colour = "0.7 setgray";
} else {
colour = "1 setgray";
}
break;
default /* case CM_FOURCOLOUR */: {
/*
* Determine the colour of this tile by translating the
* fixed colour from fourcolours[] through our current
* FourColourMap.
*/
FourColourMap f = ctx->fourcolourmap[ctx->kiteenum->curr_index];
const int *m = fourcolours[hc->c[3].type];
static const char *const colours[] = {
"1 0.7 0.7 setrgbcolor",
"1 1 0.7 setrgbcolor",
"0.7 1 0.7 setrgbcolor",
"0.6 0.6 1 setrgbcolor",
};
colour = colours[f.map[m[hc->c[2].index * 4 + hc->c[1].index]]];
break;
}
}
printf(" %s fill grestore", colour);
printf(" stroke\n");
break;
}
case OF_SVG: {
const char *class;
switch (ctx->colourmode) {
case CM_SEMANTIC: {
static const char *const classes[] = {"H", "T", "P", "F"};
if (hc->c[2].type == TT_H && hc->c[1].index == 3)
class = "H3";
else
class = classes[hc->c[2].type];
break;
}
default /* case CM_FOURCOLOUR */: {
static const char *const classes[] = {"c0", "c1", "c2", "c3"};
FourColourMap f = ctx->fourcolourmap[ctx->kiteenum->curr_index];
const int *m = fourcolours[hc->c[3].type];
class = classes[f.map[m[hc->c[2].index * 4 + hc->c[1].index]]];
break;
}
}
printf("<path class=\"%s\" d=\"", class);
for (i = 0; i < 14; i++) {
p.x = coords[2*i] * 1.5;
p.y = coords[2*i+1] * sqrt(0.75);
printf("%s %f %f", i == 0 ? "M" : " L",
ctx->xoff + ctx->xscale * p.x,
ctx->yoff + ctx->yscale * p.y);
}
printf(" z\"/>\n");
break;
}
case OF_PYTHON: {
printf("hat('%c', %d, %d, [", "HTPF"[hc->c[2].type], hc->c[1].index,
orientation);
for (i = 0; i < 14; i++)
printf("%s(%d,%d)", i ? ", " : "", coords[2*i], coords[2*i+1]);
printf("])\n");
break;
}
}
}
static void trailer(drawctx *dctx)
{
switch (dctx->outfmt) {
case OF_POSTSCRIPT: {
printf("showpage\n");
printf("%%%%Trailer\n");
printf("%%%%EOF\n");
break;
}
case OF_SVG: {
printf("</svg>\n");
break;
}
default:
break;
}
}
int main(int argc, char **argv)
{
psbbox bbox[1];
KiteEnum s[1];
HatContext ctx[1];
HatCoords *coords[KE_NKEEP];
random_state *rs;
const char *random_seed = "12345";
int w = 10, h = 10;
int argpos = 0;
size_t i;
drawctx dctx[1];
dctx->outfmt = OF_POSTSCRIPT;
dctx->colourmode = CM_SEMANTIC;
dctx->natural_scale = false;
dctx->clip = false;
dctx->kiteenum = s;
while (--argc > 0) {
const char *arg = *++argv;
if (!strcmp(arg, "--help")) {
printf(" usage: hat-test [options] [<width>] [<height>]\n"
"options: --python write a Python function call per hat\n"
" --seed=STR vary the starting random seed\n"
" also: hat-test --test\n");
return 0;
} else if (!strcmp(arg, "--test")) {
return unit_tests() ? 0 : 1;
} else if (!strcmp(arg, "--svg")) {
dctx->outfmt = OF_SVG;
} else if (!strcmp(arg, "--python")) {
dctx->outfmt = OF_PYTHON;
} else if (!strcmp(arg, "--fourcolour")) {
dctx->colourmode = CM_FOURCOLOUR;
} else if (!strcmp(arg, "--unscaled")) {
dctx->natural_scale = true;
} else if (!strcmp(arg, "--clip")) {
dctx->clip = true;
} else if (!strncmp(arg, "--seed=", 7)) {
random_seed = arg+7;
} else if (arg[0] == '-') {
fprintf(stderr, "unrecognised option '%s'\n", arg);
return 1;
} else {
switch (argpos++) {
case 0:
w = atoi(arg);
break;
case 1:
h = atoi(arg);
break;
default:
fprintf(stderr, "unexpected extra argument '%s'\n", arg);
return 1;
}
}
}
for (i = 0; i < lenof(coords); i++)
coords[i] = NULL;
rs = random_new(random_seed, strlen(random_seed));
hatctx_init_random(ctx, rs);
bbox->started = false;
dctx->bbox = bbox;
hat_kiteenum_first(s, w, h);
coords[s->curr_index] = hatctx_initial_coords(ctx);
maybe_report_hat(w, h, *s->curr, coords[s->curr_index],
bbox_add_hat, dctx);
while (hat_kiteenum_next(s)) {
hat_coords_free(coords[s->curr_index]);
coords[s->curr_index] = hatctx_step(
ctx, coords[s->last_index], s->last_step);
maybe_report_hat(w, h, *s->curr, coords[s->curr_index],
bbox_add_hat, dctx);
}
for (i = 0; i < lenof(coords); i++) {
hat_coords_free(coords[i]);
coords[i] = NULL;
}
header(dctx);
hat_kiteenum_first(s, w, h);
coords[s->curr_index] = hatctx_initial_coords(ctx);
dctx->fourcolourmap[s->curr_index] = fourcolourmap_initial(rs);
maybe_report_hat(w, h, *s->curr, coords[s->curr_index],
draw_hat, dctx);
while (hat_kiteenum_next(s)) {
hat_coords_free(coords[s->curr_index]);
coords[s->curr_index] = hatctx_step(
ctx, coords[s->last_index], s->last_step);
dctx->fourcolourmap[s->curr_index] = fourcolourmap_update(
dctx->fourcolourmap[s->last_index], coords[s->last_index],
coords[s->curr_index], s->last_step, ctx);
maybe_report_hat(w, h, *s->curr, coords[s->curr_index],
draw_hat, dctx);
}
for (i = 0; i < lenof(coords); i++) {
hat_coords_free(coords[i]);
coords[i] = NULL;
}
trailer(dctx);
hatctx_cleanup(ctx);
random_free(rs);
return 0;
}