diff options
Diffstat (limited to 'symbols/symbols-tool.c')
| -rw-r--r-- | symbols/symbols-tool.c | 881 |
1 files changed, 881 insertions, 0 deletions
diff --git a/symbols/symbols-tool.c b/symbols/symbols-tool.c new file mode 100644 index 0000000..a94feb3 --- /dev/null +++ b/symbols/symbols-tool.c @@ -0,0 +1,881 @@ +#define _POSIX_C_SOURCE 200809L +/* vega-symbols: build symbol files from fonts and SVG icons, and measure them + * against FreeType (docs/design/002-symbol-format.md). + * vega-symbols build [--font FONT.ttf --codes 0x20-0x7e,...] [--svg CODE=ICON.svg ...] [--units N] -o OUT.vsym + * vega-symbols compare FONT.ttf OUT.vsym --sizes 12,16,32,64 + * vega-symbols info OUT.vsym + * vega-symbols render OUT.vsym CODE PIXELS OUT.pgm + * vega-symbols gpu OUT.vsym --sizes 12,16,32,64 [--frames N] */ +#include "symbols-gl.h" +#include "symbols.h" +#include <EGL/egl.h> +#include <EGL/eglext.h> +#include <ft2build.h> +#include FT_FREETYPE_H +#include FT_OUTLINE_H +#include <math.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> + +#define PI 3.14159265358979323846 + +typedef struct { double x, y; } Point; +/* An outline as the pen drew it. smooth: the end lies halfway between this + * control and the next, by construction, so it may go unwritten. */ +typedef enum { MOVE, LINE, QUAD } Kind; +typedef struct { Kind kind; bool smooth; Point control, end; } Segment; +typedef struct { Segment *items; size_t count, capacity; Point at, start; bool open; double font_scale; } Path; +typedef struct { uint32_t code; size_t first, count; int16_t advance; } Built; /* segments [first, first + count) */ + +static void fail(const char *why) { + fprintf(stderr, "vega-symbols: %s\n", why); + exit(1); +} + +static void add(Path *path, Segment segment) { + if (path->count == path->capacity) { + path->capacity = path->capacity ? 2 * path->capacity : 64; + if (!(path->items = realloc(path->items, path->capacity * sizeof(*path->items)))) fail("out of memory"); + } + path->items[path->count++] = segment; + path->at = segment.end; +} + +static bool same(Point a, Point b) { return a.x == b.x && a.y == b.y; } + +static void line_to(Path *path, Point to) { + if (!same(to, path->at)) add(path, (Segment){LINE, false, to, to}); +} + +static void quad_to(Path *path, Point control, Point to) { add(path, (Segment){QUAD, false, control, to}); } + +static Point lerp(Point a, Point b, double t) { return (Point){a.x + (b.x - a.x) * t, a.y + (b.y - a.y) * t}; } +static double length(double x, double y) { return sqrt(x * x + y * y); } + +/* Whether the cubic of these differences stays within tolerance of zero + * (split in halves until its control points do). */ +static bool fits(Point p0, Point p1, Point p2, Point p3, double tolerance) { + if (length(p1.x, p1.y) <= tolerance && length(p2.x, p2.y) <= tolerance) return true; + Point mid = {(p0.x + 3 * (p1.x + p2.x) + p3.x) / 8, (p0.y + 3 * (p1.y + p2.y) + p3.y) / 8}; + if (length(mid.x, mid.y) > tolerance) return false; + Point d = {(p3.x + p2.x - p1.x - p0.x) / 8, (p3.y + p2.y - p1.y - p0.y) / 8}; + return fits(p0, lerp(p0, p1, 0.5), (Point){mid.x - d.x, mid.y - d.y}, mid, tolerance) && + fits(mid, (Point){mid.x + d.x, mid.y + d.y}, lerp(p2, p3, 0.5), p3, tolerance); +} + +/* The piece of cubic c over [a, b], as a cubic. */ +static void piece(const Point c[4], double a, double b, Point out[4]) { + Point q[4]; + for (int k = 0; k < 2; ++k) { + double t = k ? b : a, u = 1 - t; + Point e = {u * u * u * c[0].x + 3 * u * u * t * c[1].x + 3 * u * t * t * c[2].x + t * t * t * c[3].x, + u * u * u * c[0].y + 3 * u * u * t * c[1].y + 3 * u * t * t * c[2].y + t * t * t * c[3].y}; + Point d = {3 * (u * u * (c[1].x - c[0].x) + 2 * u * t * (c[2].x - c[1].x) + t * t * (c[3].x - c[2].x)), + 3 * (u * u * (c[1].y - c[0].y) + 2 * u * t * (c[2].y - c[1].y) + t * t * (c[3].y - c[2].y))}; + double h = (b - a) / 3 * (k ? -1 : 1); + q[3 * k] = e; + q[1 + k] = (Point){e.x + d.x * h, e.y + d.y * h}; + } + memcpy(out, q, sizeof(q)); +} + +/* A cubic as a quadratic spline whose joins lie halfway between neighbouring + * controls (so they go unwritten), within tolerance: the approach of cu2qu + * (fontTools). With n pieces, piece i takes its control on the line between + * the points where the cubic's end tangents reach 1.5 times their control + * arms, at i / (n - 1); the fewest pieces that fit win. */ +static bool spline(const Point c[4], int n, double tolerance, Point *controls) { + if (n == 1) { + /* One quadratic: its control where the end tangents meet. */ + Point a = {c[1].x - c[0].x, c[1].y - c[0].y}, b = {c[2].x - c[3].x, c[2].y - c[3].y}; + double cross = a.x * b.y - a.y * b.x; + if (fabs(cross) < 1e-12) return false; + double t = ((c[3].x - c[0].x) * b.y - (c[3].y - c[0].y) * b.x) / cross; + controls[0] = (Point){c[0].x + a.x * t, c[0].y + a.y * t}; + Point q1 = lerp(c[0], controls[0], 2.0 / 3), q2 = lerp(c[3], controls[0], 2.0 / 3); + return fits((Point){0, 0}, (Point){q1.x - c[1].x, q1.y - c[1].y}, (Point){q2.x - c[2].x, q2.y - c[2].y}, + (Point){0, 0}, tolerance); + } + Point from = c[0], before = {0, 0}; + for (int i = 0; i < n; ++i) { + Point p[4]; + piece(c, (double)i / n, (double)(i + 1) / n, p); + Point near = lerp(p[0], p[1], 1.5), far = lerp(p[3], p[2], 1.5); + controls[i] = lerp(near, far, (double)i / (n - 1)); + } + for (int i = 0; i < n; ++i) { + Point p[4]; + piece(c, (double)i / n, (double)(i + 1) / n, p); + Point to = i + 1 < n ? lerp(controls[i], controls[i + 1], 0.5) : c[3]; + Point after = {to.x - p[3].x, to.y - p[3].y}; + Point q1 = lerp(from, controls[i], 2.0 / 3), q2 = lerp(to, controls[i], 2.0 / 3); + if (length(after.x, after.y) > tolerance || + !fits(before, (Point){q1.x - p[1].x, q1.y - p[1].y}, (Point){q2.x - p[2].x, q2.y - p[2].y}, after, tolerance)) + return false; + from = to; + before = after; + } + return true; +} + +static void cubic_to(Path *path, Point c1, Point c2, Point to) { + Point c[4] = {path->at, c1, c2, to}, controls[64]; + if (same(c[0], c1) && same(c1, c2) && same(c2, to)) return; + for (int n = 1; n <= 64; ++n) + if (spline(c, n, 1, controls)) { + for (int i = 0; i < n; ++i) + add(path, (Segment){QUAD, i + 1 < n, controls[i], i + 1 < n ? lerp(controls[i], controls[i + 1], 0.5) : to}); + return; + } + fail("a cubic that 64 quadratics do not fit"); +} + +static void close_path(Path *path) { + if (path->open) { + line_to(path, path->start); + /* A contour of a move alone draws nothing: drop it. */ + if (path->count && path->items[path->count - 1].kind == MOVE) --path->count; + } + path->open = false; +} + +static void move_to(Path *path, Point to) { + close_path(path); + add(path, (Segment){MOVE, false, to, to}); + path->start = to; + path->open = true; +} + +/* ---- Fonts, through FreeType's outline walk (in its units, times font_scale). */ + +static Point point_of(const Path *path, const FT_Vector *v) { + return (Point){(double)v->x * path->font_scale, (double)v->y * path->font_scale}; +} +static int ft_move(const FT_Vector *to, void *user) { move_to(user, point_of(user, to)); return 0; } +static int ft_line(const FT_Vector *to, void *user) { line_to(user, point_of(user, to)); return 0; } +static int ft_conic(const FT_Vector *c, const FT_Vector *to, void *user) { + quad_to(user, point_of(user, c), point_of(user, to)); + return 0; +} +static int ft_cubic(const FT_Vector *c1, const FT_Vector *c2, const FT_Vector *to, void *user) { + cubic_to(user, point_of(user, c1), point_of(user, c2), point_of(user, to)); + return 0; +} + +/* ---- SVG icons: the d of each path, the viewBox's height as the em. */ + +static const char *number(const char *p, double *out) { + while (*p == ' ' || *p == ',' || *p == '\n' || *p == '\t' || *p == '\r') ++p; + char *end; + *out = strtod(p, &end); + return end == p ? NULL : end; +} + +/* An arc's flags are single digits, perhaps with no space between them. */ +static const char *flag(const char *p, double *out) { + while (*p == ' ' || *p == ',' || *p == '\n' || *p == '\t' || *p == '\r') ++p; + if (*p != '0' && *p != '1') return NULL; + *out = *p - '0'; + return p + 1; +} + +typedef struct { double x, y, width, height, scale; } Box; + +static Point svg_point(const Box *box, double x, double y) { + return (Point){(x - box->x) * box->scale, (box->y + box->height - y) * box->scale}; +} + +/* An elliptical arc from (x1, y1) to (x2, y2) as cubics of at most a quarter + * turn each (SVG 1.1, F.6.5: from its endpoints to its center). */ +static void arc_to(Path *path, const Box *box, double x1, double y1, double rx, double ry, double degrees, bool large, + bool sweep, double x2, double y2) { + rx = fabs(rx); + ry = fabs(ry); + if ((x1 == x2 && y1 == y2)) return; + if (!rx || !ry) { + line_to(path, svg_point(box, x2, y2)); + return; + } + double phi = degrees * PI / 180, cp = cos(phi), sp = sin(phi); + double hx = (x1 - x2) / 2, hy = (y1 - y2) / 2, px = cp * hx + sp * hy, py = -sp * hx + cp * hy; + double lambda = px * px / (rx * rx) + py * py / (ry * ry); + if (lambda > 1) { rx *= sqrt(lambda); ry *= sqrt(lambda); } + double num = rx * rx * ry * ry - rx * rx * py * py - ry * ry * px * px, den = rx * rx * py * py + ry * ry * px * px; + double k = (large == sweep ? -1 : 1) * sqrt(fmax(num / den, 0)); + double ccx = k * rx * py / ry, ccy = -k * ry * px / rx; + double cx = cp * ccx - sp * ccy + (x1 + x2) / 2, cy = sp * ccx + cp * ccy + (y1 + y2) / 2; + double start = atan2((py - ccy) / ry, (px - ccx) / rx), turn = atan2((-py - ccy) / ry, (-px - ccx) / rx) - start; + if (sweep && turn < 0) turn += 2 * PI; + if (!sweep && turn > 0) turn -= 2 * PI; + int n = (int)ceil(fabs(turn) / (PI / 2) - 1e-9); + double step = turn / n, kappa = 4.0 / 3 * tan(step / 4); + for (int i = 0; i < n; ++i) { + double a = start + i * step, b = a + step; + double u[4][2] = {{cos(a), sin(a)}, {cos(a) - kappa * sin(a), sin(a) + kappa * cos(a)}, + {cos(b) + kappa * sin(b), sin(b) - kappa * cos(b)}, {cos(b), sin(b)}}; + Point q[4]; + for (int j = 0; j < 4; ++j) + q[j] = svg_point(box, cx + rx * cp * u[j][0] - ry * sp * u[j][1], cy + rx * sp * u[j][0] + ry * cp * u[j][1]); + if (i == n - 1) q[3] = svg_point(box, x2, y2); + cubic_to(path, q[1], q[2], q[3]); + } +} + +static void svg_path(Path *path, const Box *box, const char *d) { + double cx = 0, cy = 0, sx = 0, sy = 0, lx = 0, ly = 0; /* current, subpath start, last control */ + char command = 0, last = 0; + for (const char *p = d; *p;) { + while (*p == ' ' || *p == ',' || *p == '\n' || *p == '\t' || *p == '\r') ++p; + if (!*p) break; + if (strchr("MmLlHhVvQqTtCcSsZzAa", *p)) command = *p++; + else if (!command) fail("SVG path data without a command"); + bool relative = command >= 'a'; + double ox = relative ? cx : 0, oy = relative ? cy : 0, v[7]; + char upper = (char)(command & ~32); + int want = upper == 'M' || upper == 'L' || upper == 'T' ? 2 : upper == 'H' || upper == 'V' ? 1 : + upper == 'Q' || upper == 'S' ? 4 : upper == 'C' ? 6 : upper == 'A' ? 7 : 0; + for (int i = 0; i < want; ++i) + if (!(p = (upper == 'A' && (i == 3 || i == 4) ? flag : number)(p, &v[i]))) fail("SVG path data"); + switch (upper) { + case 'Z': + close_path(path); + cx = sx; cy = sy; + path->at = svg_point(box, cx, cy); + command = 0; /* a number after closepath is an error */ + break; + case 'A': { + double x = ox + v[5], y = oy + v[6]; + arc_to(path, box, cx, cy, v[0], v[1], v[2], v[3] != 0, v[4] != 0, x, y); + cx = x; cy = y; + break; + } + case 'M': + cx = ox + v[0]; cy = oy + v[1]; sx = cx; sy = cy; + move_to(path, svg_point(box, cx, cy)); + command = relative ? 'l' : 'L'; /* pairs after a moveto are linetos */ + break; + case 'L': cx = ox + v[0]; cy = oy + v[1]; line_to(path, svg_point(box, cx, cy)); break; + case 'H': cx = ox + v[0]; line_to(path, svg_point(box, cx, cy)); break; + case 'V': cy = (relative ? cy : 0) + v[0]; line_to(path, svg_point(box, cx, cy)); break; + case 'Q': + lx = ox + v[0]; ly = oy + v[1]; cx = ox + v[2]; cy = oy + v[3]; + quad_to(path, svg_point(box, lx, ly), svg_point(box, cx, cy)); + break; + case 'T': + lx = last == 'Q' || last == 'T' ? 2 * cx - lx : cx; ly = last == 'Q' || last == 'T' ? 2 * cy - ly : cy; + cx = ox + v[0]; cy = oy + v[1]; + quad_to(path, svg_point(box, lx, ly), svg_point(box, cx, cy)); + break; + case 'C': case 'S': { + double x1, y1; + if (upper == 'C') { x1 = ox + v[0]; y1 = oy + v[1]; } + else { x1 = last == 'C' || last == 'S' ? 2 * cx - lx : cx; y1 = last == 'C' || last == 'S' ? 2 * cy - ly : cy; } + int at = upper == 'C' ? 2 : 0; + lx = ox + v[at]; ly = oy + v[at + 1]; + double x = ox + v[at + 2], y = oy + v[at + 3]; + cubic_to(path, svg_point(box, x1, y1), svg_point(box, lx, ly), svg_point(box, x, y)); + cx = x; cy = y; + break; + } + } + last = upper; + } + close_path(path); +} + +static char *read_file(const char *name, size_t *size) { + FILE *f = fopen(name, "rb"); + if (!f) return NULL; + fseek(f, 0, SEEK_END); + long length = ftell(f); + fseek(f, 0, SEEK_SET); + char *bytes = length >= 0 ? malloc((size_t)length + 1) : NULL; + if (bytes && fread(bytes, 1, (size_t)length, f) != (size_t)length) { free(bytes); bytes = NULL; } + fclose(f); + if (bytes) { bytes[length] = 0; *size = (size_t)length; } + return bytes; +} + +static const char *attribute(const char *from, const char *end, const char *name) { + size_t length = strlen(name); + for (const char *p = from; p && p < end; ++p) { + p = strstr(p, name); + if (!p || p >= end) return NULL; + if ((p == from || p[-1] == ' ' || p[-1] == '\n' || p[-1] == '\t') && p[length] == '=' && + (p[length + 1] == '"' || p[length + 1] == '\'')) return p + length + 2; + } + return NULL; +} + +/* Only solid, nonzero-filled paths: anything else an icon asks for would be + * drawn wrong, so it is refused rather than dropped. */ +static const char *const unsupported[] = {"transform", "opacity", "evenodd", "stroke", "fill=\"none\"", "<use", + "<rect", "<circle", "<ellipse", "<poly", "<line", "<radial", "<clip", + "<mask", "<image", "<text", "<filter", "<pattern"}; + +static void svg_icon(Path *path, const char *file, uint16_t units, int16_t *advance) { + size_t size; + char *svg = read_file(file, &size), why[512]; + if (!svg) fail("cannot read an SVG file"); + for (size_t i = 0; i < sizeof(unsupported) / sizeof(*unsupported); ++i) + if (strstr(svg, unsupported[i])) { + snprintf(why, sizeof(why), "%s: icons hold only solid paths, not %s", file, unsupported[i]); + fail(why); + } + const char *tag = strstr(svg, "<svg"), *tag_end = tag ? strchr(tag, '>') : NULL, *view = tag ? attribute(tag, tag_end, "viewBox") : NULL; + /* Without a viewBox, the width and height (in px) are the user space. */ + Box box = {0}; + const char *width = tag ? attribute(tag, tag_end, "width") : NULL, *height = tag ? attribute(tag, tag_end, "height") : NULL; + if (view ? !(view = number(view, &box.x)) || !(view = number(view, &box.y)) || !(view = number(view, &box.width)) || + !number(view, &box.height) + : !width || !height || !number(width, &box.width) || !number(height, &box.height) || box.height <= 0) { + snprintf(why, sizeof(why), "%s: an icon needs a viewBox, or a width and height", file); + fail(why); + } + box.scale = units / box.height; + *advance = (int16_t)lround(box.width * box.scale); + for (const char *p = svg; (p = strstr(p, "<path"));) { + const char *end = strchr(p, '>'), *d = attribute(p, end, "d"); + if (d) { + char quote = d[-1]; + const char *close = strchr(d, quote); + char *data = strndup(d, (size_t)(close - d)); + svg_path(path, &box, data); + free(data); + } + p = end ? end : p + 5; + } + free(svg); +} + +/* ---- Writing. */ + +typedef struct { long x, y; bool off, move; } Emitted; +typedef struct { Emitted *items; size_t count, capacity; } Points; + +static void put16(unsigned char *p, int v) { p[0] = (unsigned char)v; p[1] = (unsigned char)((unsigned)v >> 8); } +static void put32(unsigned char *p, uint32_t v) { for (int i = 0; i < 4; ++i) p[i] = (unsigned char)(v >> (8 * i)); } + +static void emit(Points *points, Point at, bool off, bool move) { + if (points->count == points->capacity) { + points->capacity = points->capacity ? 2 * points->capacity : 256; + if (!(points->items = realloc(points->items, points->capacity * sizeof(*points->items)))) fail("out of memory"); + } + points->items[points->count++] = (Emitted){lround(at.x), lround(at.y), off, move}; +} + +/* Whether s ends where its control and the next curve's would imply. */ +static bool implied(const Segment *s, const Segment *next) { + if (s->kind != QUAD || !next || next->kind != QUAD) return false; + return s->smooth || (2 * lround(s->end.x) == lround(s->control.x) + lround(next->control.x) && + 2 * lround(s->end.y) == lround(s->control.y) + lround(next->control.y)); +} + +/* One symbol's segments as points: each contour an on point that starts it, + * then per segment its control (if a curve) and its end, unless the next + * curve's control implies it; the last end, back at the start, is written. + * A contour that starts at an implied point (as FreeType starts TrueType's + * when its first point is off) starts instead at its first written one. */ +static void emit_symbol(Points *points, const Segment *segments, size_t count) { + for (size_t i = 0; i < count;) { + size_t end = i + 1; + while (end < count && segments[end].kind != MOVE) ++end; + const Segment *body = segments + i + 1; + size_t n = end - i - 1, from = 0; + if (n > 1 && implied(&body[n - 1], &body[0])) + for (size_t k = 0; k + 1 < n; ++k) + if (!implied(&body[k], &body[k + 1])) { from = k + 1; break; } + emit(points, from ? body[from - 1].end : segments[i].end, false, true); + for (size_t m = 0; m < n; ++m) { + const Segment *s = &body[(from + m) % n], *next = m + 1 < n ? &body[(from + m + 1) % n] : NULL; + const Emitted *last = &points->items[points->count - 1]; + if (s->kind == LINE) { + if (last->off || last->x != lround(s->end.x) || last->y != lround(s->end.y)) emit(points, s->end, false, false); + continue; + } + emit(points, s->control, true, false); + if (!implied(s, next)) emit(points, s->end, false, false); + } + i = end; + } +} + +static int by_code(const void *a, const void *b) { + uint32_t x = ((const Built *)a)->code, y = ((const Built *)b)->code; + return (x > y) - (x < y); +} + +static void write_symbols(const char *out, uint16_t units, Built *built, size_t count, const Path *path) { + qsort(built, count, sizeof(*built), by_code); + for (size_t i = 1; i < count; ++i) if (built[i].code == built[i - 1].code) fail("a code is given twice"); + Points points = {0}; + size_t *first = calloc(count + 1, sizeof(*first)); + for (size_t i = 0; i < count; ++i) { + first[i] = points.count; + emit_symbol(&points, path->items + built[i].first, built[i].count); + } + first[count] = points.count; + /* Halve units while every coordinate is even: a TrueType font's own. */ + for (;;) { + bool even = units % 2 == 0 && units > 16; + for (size_t i = 0; even && i < points.count; ++i) even = points.items[i].x % 2 == 0 && points.items[i].y % 2 == 0; + for (size_t i = 0; even && i < count; ++i) even = built[i].advance % 2 == 0; + if (!even) break; + for (size_t i = 0; i < points.count; ++i) { points.items[i].x /= 2; points.items[i].y /= 2; } + for (size_t i = 0; i < count; ++i) built[i].advance = (int16_t)(built[i].advance / 2); + units /= 2; + } + size_t size = VEGA_SYMBOLS_HEADER + count * VEGA_SYMBOL_BYTES + points.count * VEGA_POINT_BYTES; + unsigned char *bytes = calloc(1, size); + if (!bytes) fail("out of memory"); + memcpy(bytes, "VEGASYM2", 8); + put16(bytes + 8, units); + put32(bytes + 12, (uint32_t)count); + put32(bytes + 16, (uint32_t)points.count); + put32(bytes + 20, (uint32_t)size); + unsigned char *at = bytes + VEGA_SYMBOLS_HEADER + count * VEGA_SYMBOL_BYTES; + for (size_t i = 0; i < points.count; ++i) { + const Emitted *e = &points.items[i]; + if (e->x < -16384 || e->x > 16383 || e->y < -16384 || e->y > 16383) fail("a coordinate does not fit 15 bits"); + put16(at + 4 * i, (int)(2 * e->x + e->off)); + put16(at + 4 * i + 2, (int)(2 * e->y + e->move)); + } + for (size_t i = 0; i < count; ++i) { + long left = 0, bottom = 0, right = 0, top = 0; + for (size_t k = first[i]; k < first[i + 1]; ++k) { + const Emitted *e = &points.items[k]; + if (k == first[i]) { left = right = e->x; bottom = top = e->y; } + left = e->x < left ? e->x : left; + right = e->x > right ? e->x : right; + bottom = e->y < bottom ? e->y : bottom; + top = e->y > top ? e->y : top; + } + unsigned char *p = bytes + VEGA_SYMBOLS_HEADER + i * VEGA_SYMBOL_BYTES; + put32(p, built[i].code); + put32(p + 4, (uint32_t)first[i]); + put32(p + 8, (uint32_t)(first[i + 1] - first[i])); + put16(p + 12, (int)left); + put16(p + 14, (int)bottom); + put16(p + 16, (int)right); + put16(p + 18, (int)top); + put16(p + 20, built[i].advance); + } + FILE *f = fopen(out, "wb"); + if (!f || fwrite(bytes, 1, size, f) != size || fclose(f)) fail("cannot write the symbol file"); + char error[128]; + VegaSymbols check; + if (!vega_symbols_open(&check, bytes, size, error, sizeof(error))) fail(error); + size_t curves = 0; + VegaCurve curve; + for (uint32_t i = 0; i < check.symbols; ++i) { + VegaSymbol symbol = vega_symbol_at(&check, i); + for (uint32_t k = symbol.first; k < symbol.first + symbol.count; ++k) curves += vega_symbol_curve(&check, &symbol, k, &curve); + } + printf("{\"symbols\":%zu,\"points\":%zu,\"curves\":%zu,\"units\":%u,\"bytes\":%zu}\n", count, points.count, curves, + units, size); + free(bytes); + free(first); + free(points.items); +} + +/* 0x20-0x7e,0xac00 as a list of codes. */ +static size_t codes_of(const char *text, uint32_t **out) { + size_t count = 0, capacity = 0; + *out = NULL; + for (const char *p = text; *p;) { + char *end; + unsigned long first = strtoul(p, &end, 0), last = first; + if (end == p) fail("--codes takes FIRST[-LAST],..."); + p = end; + if (*p == '-') { last = strtoul(p + 1, &end, 0); p = end; } + for (unsigned long c = first; c <= last; ++c) { + if (count == capacity && !(*out = realloc(*out, (capacity = capacity ? 2 * capacity : 256) * sizeof(**out)))) + fail("out of memory"); + (*out)[count++] = (uint32_t)c; + } + if (*p == ',') ++p; + } + return count; +} + +static double seconds(void) { + struct timespec t; + clock_gettime(CLOCK_MONOTONIC, &t); + return (double)t.tv_sec + (double)t.tv_nsec / 1e9; +} + +#define BUILD_USAGE "usage: vega-symbols build [--font FONT.ttf --codes 0x20-0x7e,...] [--svg CODE=ICON.svg ...] [--units N] -o OUT.vsym" + +static int build(int argc, char **argv) { + const char *font = NULL, *out = NULL, *codes = NULL, **icons = calloc((size_t)argc, sizeof(*icons)); + size_t icon_count = 0; + long units = 0; + for (int i = 2; i < argc; i += 2) { + if (i + 1 == argc) fail(BUILD_USAGE); + if (!strcmp(argv[i], "-o")) out = argv[i + 1]; + else if (!strcmp(argv[i], "--font")) font = argv[i + 1]; + else if (!strcmp(argv[i], "--codes")) codes = argv[i + 1]; + else if (!strcmp(argv[i], "--units")) units = strtol(argv[i + 1], NULL, 10); + else if (!strcmp(argv[i], "--svg")) icons[icon_count++] = argv[i + 1]; + else fail(BUILD_USAGE); + } + if (!out || !font != !codes) fail(BUILD_USAGE); + FT_Library library = NULL; + FT_Face face = NULL; + if (font && (FT_Init_FreeType(&library) || FT_New_Face(library, font, 0, &face))) fail("cannot open the font"); + /* Twice a font's units by default: TrueType's implied points, halfway + * between two control points, then land on whole units. (FreeType finds + * them by integer halving, so outlines are doubled before it walks them.) */ + if (!units) units = face ? 2 * face->units_per_EM : 4096; + if (units < 16 || units > 16384) fail("--units: 16 to 16384"); + uint32_t *list = NULL; + size_t count = codes ? codes_of(codes, &list) : 0; + Built *built = calloc(count + icon_count + 1, sizeof(*built)); + Path path = {.font_scale = face ? (double)units / (2.0 * face->units_per_EM) : 1}; + size_t made = 0; + FT_Outline_Funcs walk = {ft_move, ft_line, ft_conic, ft_cubic, 0, 0}; + for (size_t i = 0; i < count; ++i) { + FT_UInt glyph = FT_Get_Char_Index(face, list[i]); + if (!glyph || FT_Load_Glyph(face, glyph, FT_LOAD_NO_SCALE)) continue; /* the font lacks it */ + size_t first = path.count; + path.open = false; + if (face->glyph->format == FT_GLYPH_FORMAT_OUTLINE) { + FT_Outline_Transform(&face->glyph->outline, &(FT_Matrix){0x20000, 0, 0, 0x20000}); + if (FT_Outline_Decompose(&face->glyph->outline, &walk, &path)) fail("cannot walk an outline"); + } + close_path(&path); + long advance = lround((double)face->glyph->metrics.horiAdvance * units / face->units_per_EM); + built[made++] = (Built){list[i], first, path.count - first, (int16_t)(advance > INT16_MAX ? INT16_MAX : advance)}; + } + for (size_t i = 0; i < icon_count; ++i) { + char *equals = strchr(icons[i], '='); + if (!equals) fail("--svg takes CODE=FILE"); + size_t first = path.count; + path.open = false; + int16_t advance; + svg_icon(&path, equals + 1, (uint16_t)units, &advance); + built[made++] = (Built){(uint32_t)strtoul(icons[i], NULL, 0), first, path.count - first, advance}; + } + write_symbols(out, (uint16_t)units, built, made, &path); + if (face) FT_Done_Face(face); + if (library) FT_Done_FreeType(library); + free(icons); + free(list); + free(built); + free(path.items); + return 0; +} + +static VegaSymbols open_symbols(const char *name, char **bytes) { + size_t size; + char error[128]; + VegaSymbols s; + if (!(*bytes = read_file(name, &size))) fail("cannot read the symbol file"); + if (!vega_symbols_open(&s, (unsigned char *)*bytes, size, error, sizeof(error))) fail(error); + return s; +} + +static volatile long sink; /* keeps the timed loops' reads */ +static int ignore_point(const FT_Vector *to, void *user) { ++*(long *)user; (void)to; return 0; } +static int ignore_conic(const FT_Vector *c, const FT_Vector *to, void *user) { (void)c; return ignore_point(to, user); } +static int ignore_cubic(const FT_Vector *c1, const FT_Vector *c2, const FT_Vector *to, void *user) { + (void)c1; + (void)c2; + return ignore_point(to, user); +} + +/* What reading costs, both ways: opening (verifying the symbol file; parsing + * the font's tables) and reaching every symbol's outline. */ +static void measure_open(FT_Library library, const char *font, const VegaSymbols *s) { + size_t font_size; + char *font_bytes = read_file(font, &font_size), error[128]; + if (!font_bytes) fail("cannot read the font"); + int rounds = 200; + double started = seconds(); + for (int i = 0; i < rounds; ++i) { + VegaSymbols again; + if (!vega_symbols_open(&again, s->bytes, s->size, error, sizeof(error))) fail(error); + } + double open_us = (seconds() - started) / rounds * 1e6; + started = seconds(); + for (int i = 0; i < rounds; ++i) { + FT_Face face; + if (FT_New_Memory_Face(library, (const FT_Byte *)font_bytes, (FT_Long)font_size, 0, &face)) fail("cannot open the font"); + FT_Done_Face(face); + } + double freetype_open_us = (seconds() - started) / rounds * 1e6; + FT_Face face; + if (FT_New_Memory_Face(library, (const FT_Byte *)font_bytes, (FT_Long)font_size, 0, &face)) fail("cannot open the font"); + FT_Outline_Funcs walk = {ignore_point, ignore_point, ignore_conic, ignore_cubic, 0, 0}; + long touched = 0, walked = 0; + uint32_t most = 0; + for (uint32_t i = 0; i < s->symbols; ++i) most = vega_symbol_at(s, i).count > most ? vega_symbol_at(s, i).count : most; + VegaCurve *curves = malloc((most + 1) * sizeof(*curves)); + started = seconds(); + for (int r = 0; r < rounds; ++r) + for (uint32_t i = 0; i < s->symbols; ++i) { + VegaSymbol symbol; + if (!vega_symbol(s, vega_symbol_at(s, i).code, &symbol)) fail("lookup"); + uint32_t count = vega_symbol_curves(s, &symbol, curves); + touched += count ? (long)curves[count - 1].x2 : 0; + } + double outline_ns = (seconds() - started) / rounds / s->symbols * 1e9; + started = seconds(); + for (int r = 0; r < rounds; ++r) + for (uint32_t i = 0; i < s->symbols; ++i) { + FT_UInt glyph = FT_Get_Char_Index(face, vega_symbol_at(s, i).code); + if (glyph && !FT_Load_Glyph(face, glyph, FT_LOAD_NO_SCALE)) FT_Outline_Decompose(&face->glyph->outline, &walk, &walked); + } + double freetype_outline_ns = (seconds() - started) / rounds / s->symbols * 1e9; + printf("{\"symbol_bytes\":%zu,\"font_bytes\":%zu,\"open_us\":%.1f,\"freetype_open_us\":%.1f,\"outline_ns\":%.0f," + "\"freetype_outline_ns\":%.0f}\n", s->size, font_size, open_us, freetype_open_us, outline_ns, freetype_outline_ns); + sink = touched + walked; + FT_Done_Face(face); + free(font_bytes); + free(curves); +} + +/* Every symbol with a glyph in the font, at each size: our coverage against + * FreeType's (no hinting, 8-bit gray) over FreeType's bitmap. */ +static int compare(int argc, char **argv) { + if (argc < 6 || strcmp(argv[4], "--sizes")) fail("usage: vega-symbols compare FONT.ttf SYMBOLS.vsym --sizes 12,16,32,64"); + char *bytes; + VegaSymbols s = open_symbols(argv[3], &bytes); + FT_Library library; + FT_Face face; + if (FT_Init_FreeType(&library) || FT_New_Face(library, argv[2], 0, &face)) fail("cannot open the font"); + measure_open(library, argv[2], &s); + for (const char *p = argv[5]; *p;) { + char *end; + long size = strtol(p, &end, 10); + p = *end == ',' ? end + 1 : end; + if (size <= 0 || FT_Set_Pixel_Sizes(face, 0, (FT_UInt)size)) fail("--sizes"); + double scale = (double)size / s.units, total = 0, ours_seconds = 0; + uint64_t pixels = 0, close = 0; + int worst = 0, glyphs = 0; + unsigned char *raster = NULL; + size_t raster_size = 0; + for (uint32_t i = 0; i < s.symbols; ++i) { + VegaSymbol symbol = vega_symbol_at(&s, i); + FT_UInt glyph = FT_Get_Char_Index(face, symbol.code); + if (!glyph || FT_Load_Glyph(face, glyph, FT_LOAD_NO_HINTING | FT_LOAD_RENDER)) continue; + FT_Bitmap *b = &face->glyph->bitmap; + size_t need = (size_t)b->width * b->rows; + if (!need) continue; + if (need > raster_size && !(raster = realloc(raster, raster_size = need))) fail("out of memory"); + double started = seconds(); + vega_symbol_raster(&s, &symbol, scale, face->glyph->bitmap_left / scale, face->glyph->bitmap_top / scale, + (int)b->width, (int)b->rows, raster); + ours_seconds += seconds() - started; + for (unsigned j = 0; j < b->rows; ++j) + for (unsigned i2 = 0; i2 < b->width; ++i2) { + int theirs = b->buffer[j * (unsigned)b->pitch + i2], ours = raster[j * b->width + i2]; + int difference = abs(theirs - ours); + total += difference; + close += difference <= 16; + if (difference > worst) worst = difference; + ++pixels; + } + ++glyphs; + } + printf("{\"pixels_per_em\":%ld,\"glyphs\":%d,\"mean_difference\":%.2f,\"worst\":%d,\"within_16\":%.4f," + "\"reference_us_per_glyph\":%.1f}\n", size, glyphs, pixels ? total / (double)pixels : 0, worst, + pixels ? (double)close / (double)pixels : 1, glyphs ? ours_seconds / glyphs * 1e6 : 0); + free(raster); + } + FT_Done_Face(face); + FT_Done_FreeType(library); + free(bytes); + return 0; +} + +/* Each symbol's code, points, curves, bounds, advance and filled area (in square + * units: the integral of x dy around its outline, as a check against other + * readers of the same fonts and icons). */ +static int info(int argc, char **argv) { + if (argc < 3) fail("usage: vega-symbols info SYMBOLS.vsym"); + char *bytes; + VegaSymbols s = open_symbols(argv[2], &bytes); + printf("{\"units\":%u,\"symbols\":[", s.units); + for (uint32_t i = 0; i < s.symbols; ++i) { + VegaSymbol symbol = vega_symbol_at(&s, i); + double area = 0; + uint32_t curves = 0; + VegaCurve c; + for (uint32_t k = symbol.first; k < symbol.first + symbol.count; ++k) { + if (!vega_symbol_curve(&s, &symbol, k, &c)) continue; + ++curves; + /* x(t) = x0 - 2 bx t + ax t^2, y'(t) = -2 by + 2 ay t, over [0, 1]. */ + double ax = c.x0 - 2 * c.x1 + c.x2, bx = c.x0 - c.x1, ay = c.y0 - 2 * c.y1 + c.y2, by = c.y0 - c.y1; + area += c.x0 * -2 * by + (c.x0 * 2 * ay + 4 * bx * by) / 2 + (-4 * bx * ay - 2 * ax * by) / 3 + ax * ay / 2; + } + printf("%s{\"code\":%u,\"points\":%u,\"curves\":%u,\"bounds\":[%d,%d,%d,%d],\"advance\":%d,\"area\":%.1f}", + i ? "," : "", symbol.code, symbol.count, curves, symbol.left, symbol.bottom, symbol.right, symbol.top, + symbol.advance, area); + } + printf("]}\n"); + free(bytes); + return 0; +} + +static int render(int argc, char **argv) { + if (argc < 6) fail("usage: vega-symbols render SYMBOLS.vsym CODE PIXELS OUT.pgm"); + char *bytes; + VegaSymbols s = open_symbols(argv[2], &bytes); + VegaSymbol symbol; + if (!vega_symbol(&s, (uint32_t)strtoul(argv[3], NULL, 0), &symbol)) fail("no such symbol"); + double pixels = atof(argv[4]), scale = pixels / s.units; + int width = (int)ceil((symbol.advance > symbol.right ? symbol.advance : symbol.right) * scale) + 2; + int height = (int)ceil(pixels * 1.25) + 2; + unsigned char *raster = malloc((size_t)width * (size_t)height); + vega_symbol_raster(&s, &symbol, scale, -1 / scale, (pixels + 1) / scale, width, height, raster); + FILE *f = fopen(argv[5], "wb"); + if (!f) fail("cannot write"); + fprintf(f, "P5\n%d %d\n255\n", width, height); + fwrite(raster, 1, (size_t)width * (size_t)height, f); + fclose(f); + free(raster); + free(bytes); + return 0; +} + +/* ---- The GPU: a context of its own, no window (EGL, Mesa's surfaceless platform). */ + +static void gl_context(void) { + PFNEGLGETPLATFORMDISPLAYEXTPROC platform = (PFNEGLGETPLATFORMDISPLAYEXTPROC)eglGetProcAddress("eglGetPlatformDisplayEXT"); + EGLDisplay display = platform ? platform(EGL_PLATFORM_SURFACELESS_MESA, EGL_DEFAULT_DISPLAY, NULL) : EGL_NO_DISPLAY; + EGLint major, minor, found; + EGLConfig config; + EGLint wanted[] = {EGL_RENDERABLE_TYPE, EGL_OPENGL_ES3_BIT, EGL_NONE}; + EGLint version[] = {EGL_CONTEXT_MAJOR_VERSION, 3, EGL_CONTEXT_MINOR_VERSION, 1, EGL_NONE}; + if (display == EGL_NO_DISPLAY || !eglInitialize(display, &major, &minor) || !eglBindAPI(EGL_OPENGL_ES_API) || + !eglChooseConfig(display, wanted, &config, 1, &found)) + fail("no EGL display for OpenGL ES 3.1"); + /* With no surface, a context needs no config (EGL_KHR_no_config_context). */ + EGLContext context = eglCreateContext(display, found ? config : EGL_NO_CONFIG_KHR, EGL_NO_CONTEXT, version); + if (context == EGL_NO_CONTEXT || !eglMakeCurrent(display, EGL_NO_SURFACE, EGL_NO_SURFACE, context)) + fail("no OpenGL ES 3.1 context"); +} + +/* A width x height target of 8-bit red, bound. */ +static GLuint gl_target(int width, int height) { + GLuint texture, framebuffer; + glGenTextures(1, &texture); + glBindTexture(GL_TEXTURE_2D, texture); + glTexStorage2D(GL_TEXTURE_2D, 1, GL_R8, width, height); + glGenFramebuffers(1, &framebuffer); + glBindFramebuffer(GL_FRAMEBUFFER, framebuffer); + glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texture, 0); + if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) fail("no framebuffer"); + glViewport(0, 0, width, height); + glClearColor(0, 0, 0, 0); + glClear(GL_COLOR_BUFFER_BIT); + return texture; +} + +/* Every symbol in a grid of cells, drawn by the GPU and by vega_coverage: + * how far apart; then pages of text (glyphs cycling through the file) + * drawn again and again: how long a page takes. */ +static int gpu(int argc, char **argv) { + if (argc < 5 || strcmp(argv[3], "--sizes")) fail("usage: vega-symbols gpu SYMBOLS.vsym --sizes 12,16,32,64 [--frames N]"); + int frames = argc > 6 && !strcmp(argv[5], "--frames") ? atoi(argv[6]) : 20; + if (frames < 1) fail("--frames"); + char *bytes, error[4096]; + VegaSymbols s = open_symbols(argv[2], &bytes); + gl_context(); + printf("{\"renderer\":\"%s\"}\n", (const char *)glGetString(GL_RENDERER)); + VegaGl gl; + double started = seconds(); + if (!vega_gl_open(&gl, &s, error, sizeof(error))) fail(error); + glFinish(); + double open_ms = (seconds() - started) * 1e3; + for (const char *p = argv[4]; *p;) { + char *end; + long size = strtol(p, &end, 10); + p = *end == ',' ? end + 1 : end; + if (size <= 0 || size > 512) fail("--sizes"); + double scale = (double)size / s.units; + /* Cells that hold any symbol, so none reaches into another's. */ + int left = 0, bottom = 0, right = 0, top = 0; + for (uint32_t i = 0; i < s.symbols; ++i) { + VegaSymbol symbol = vega_symbol_at(&s, i); + left = symbol.left < left ? symbol.left : left; + bottom = symbol.bottom < bottom ? symbol.bottom : bottom; + right = symbol.right > right ? symbol.right : right; + top = symbol.top > top ? symbol.top : top; + } + int cell = (int)ceil((right - left > top - bottom ? right - left : top - bottom) * scale) + 4; + int across = 4096 / cell, rows = (int)((s.symbols + (uint32_t)across - 1) / (uint32_t)across); + if (rows * cell > 4096) rows = 4096 / cell; + int width = across * cell, height = rows * cell; + uint32_t shown = s.symbols < (uint32_t)(across * rows) ? s.symbols : (uint32_t)(across * rows); + VegaGlyph *glyphs = malloc(shown * sizeof(*glyphs)); + for (uint32_t i = 0; i < shown; ++i) + glyphs[i] = (VegaGlyph){(float)(i % (uint32_t)across * (uint32_t)cell) + 2 - (float)(left * scale), + (float)(i / (uint32_t)across * (uint32_t)cell) + 2 + (float)(top * scale), (float)scale, i}; + GLuint texture = gl_target(width, height); + vega_gl_draw(&gl, &s, glyphs, shown, width, height); + unsigned char *drawn = malloc((size_t)width * (size_t)height), *reference = malloc((size_t)cell * (size_t)cell); + glPixelStorei(GL_PACK_ALIGNMENT, 1); + glReadPixels(0, 0, width, height, GL_RED, GL_UNSIGNED_BYTE, drawn); + double total = 0; + uint64_t pixels = 0; + int worst = 0; + for (uint32_t i = 0; i < shown; ++i) { + VegaSymbol symbol = vega_symbol_at(&s, i); + int x0 = (int)(i % (uint32_t)across) * cell, y0 = (int)(i / (uint32_t)across) * cell; + vega_symbol_raster(&s, &symbol, scale, (x0 - glyphs[i].x) / scale, (glyphs[i].y - y0) / scale, cell, cell, reference); + for (int j = 0; j < cell; ++j) + for (int k = 0; k < cell; ++k) { + /* GL's rows run bottom up */ + int gpu_value = drawn[(size_t)(height - 1 - (y0 + j)) * (size_t)width + (size_t)(x0 + k)]; + int difference = abs(gpu_value - reference[j * cell + k]); + total += difference; + worst = difference > worst ? difference : worst; + ++pixels; + } + } + /* Pages: glyphs at their advances in lines, a full target's worth. */ + int page_width = 1920, page_height = 1080; + uint32_t page = 0, capacity = 1 << 16; + VegaGlyph *text = malloc(capacity * sizeof(*text)); + float x = 0, line = (float)size * 1.2f; + for (float y = line; y + (float)size * 0.3f < (float)page_height && page < capacity; ) { + VegaSymbol symbol = vega_symbol_at(&s, page % s.symbols); + float advance = (float)(symbol.advance * scale); + if (x + advance > (float)page_width) { x = 0; y += line; continue; } + text[page++] = (VegaGlyph){x, y, (float)scale, page % s.symbols}; + x += advance; + } + glDeleteTextures(1, &texture); + texture = gl_target(page_width, page_height); + vega_gl_draw(&gl, &s, text, page, page_width, page_height); + glFinish(); + started = seconds(); + for (int f = 0; f < frames; ++f) vega_gl_draw(&gl, &s, text, page, page_width, page_height); + glFinish(); + double page_ms = (seconds() - started) / frames * 1e3; + printf("{\"pixels_per_em\":%ld,\"symbols\":%u,\"mean_difference\":%.3f,\"worst\":%d,\"page_glyphs\":%u," + "\"page_ms\":%.2f,\"upload_ms\":%.1f}\n", size, shown, pixels ? total / (double)pixels : 0, worst, page, page_ms, open_ms); + glDeleteTextures(1, &texture); + free(text); + free(glyphs); + free(drawn); + free(reference); + } + vega_gl_close(&gl); + free(bytes); + return 0; +} + +int main(int argc, char **argv) { + if (argc > 1 && !strcmp(argv[1], "build")) return build(argc, argv); + if (argc > 1 && !strcmp(argv[1], "compare")) return compare(argc, argv); + if (argc > 1 && !strcmp(argv[1], "info")) return info(argc, argv); + if (argc > 1 && !strcmp(argv[1], "render")) return render(argc, argv); + if (argc > 1 && !strcmp(argv[1], "gpu")) return gpu(argc, argv); + fail("vega-symbols build|compare|info|render|gpu ..."); + return 2; +} |