From 318ae7fe1bd614cb937c8f43d855a1c2e8e93fd4 Mon Sep 17 00:00:00 2001 From: "Avi Halachmi (:avih)" Date: Wed, 26 Dec 2018 14:51:45 +0200 Subject: [PATCH] boxdraw_v2: custom render lines/blocks/braille for perfect alignment It seems impossible to ensure that blocks and line drawing glyphs align without visible gaps for all combinations of arbitrary font, size and width/height scale factor. This commit adds options to render most of the lines/blocks and braille codepoints without using the font such that they align perfectly regardless of font, size or other configuration values. Supported codepoints are U+2500 - U+259F except dashes/diagonals, and U28XX. The lines/blocks data is stored as 16-bit values at boxdraw_data.h boxdraw/braille are independent, disabled by default at config[.def].h --- Makefile | 3 +- boxdraw.c | 194 ++++++++++++++++++++++++++++++++++++++++++++ boxdraw_data.h | 214 +++++++++++++++++++++++++++++++++++++++++++++++++ config.def.h | 12 +++ st.c | 3 + st.h | 10 +++ x.c | 21 +++-- 7 files changed, 451 insertions(+), 6 deletions(-) create mode 100644 boxdraw.c create mode 100644 boxdraw_data.h diff --git a/Makefile b/Makefile index 470ac86..6dfa212 100644 --- a/Makefile +++ b/Makefile @@ -4,7 +4,7 @@ include config.mk -SRC = st.c x.c +SRC = st.c x.c boxdraw.c OBJ = $(SRC:.c=.o) all: options st @@ -23,6 +23,7 @@ config.h: st.o: config.h st.h win.h x.o: arg.h config.h st.h win.h +boxdraw.o: config.h st.h boxdraw_data.h $(OBJ): config.h config.mk diff --git a/boxdraw.c b/boxdraw.c new file mode 100644 index 0000000..28a92d0 --- /dev/null +++ b/boxdraw.c @@ -0,0 +1,194 @@ +/* + * Copyright 2018 Avi Halachmi (:avih) avihpit@yahoo.com https://github.com/avih + * MIT/X Consortium License + */ + +#include +#include "st.h" +#include "boxdraw_data.h" + +/* Rounded non-negative integers division of n / d */ +#define DIV(n, d) (((n) + (d) / 2) / (d)) + +static Display *xdpy; +static Colormap xcmap; +static XftDraw *xd; +static Visual *xvis; + +static void drawbox(int, int, int, int, XftColor *, XftColor *, ushort); +static void drawboxlines(int, int, int, int, XftColor *, ushort); + +/* public API */ + +void +boxdraw_xinit(Display *dpy, Colormap cmap, XftDraw *draw, Visual *vis) +{ + xdpy = dpy; xcmap = cmap; xd = draw, xvis = vis; +} + +int +isboxdraw(Rune u) +{ + Rune block = u & ~0xff; + return (boxdraw && block == 0x2500 && boxdata[(uint8_t)u]) || + (boxdraw_braille && block == 0x2800); +} + +/* the "index" is actually the entire shape data encoded as ushort */ +ushort +boxdrawindex(const Glyph *g) +{ + if (boxdraw_braille && (g->u & ~0xff) == 0x2800) + return BRL | (uint8_t)g->u; + if (boxdraw_bold && (g->mode & ATTR_BOLD)) + return BDB | boxdata[(uint8_t)g->u]; + return boxdata[(uint8_t)g->u]; +} + +void +drawboxes(int x, int y, int cw, int ch, XftColor *fg, XftColor *bg, + const XftGlyphFontSpec *specs, int len) +{ + for ( ; len-- > 0; x += cw, specs++) + drawbox(x, y, cw, ch, fg, bg, (ushort)specs->glyph); +} + +/* implementation */ + +void +drawbox(int x, int y, int w, int h, XftColor *fg, XftColor *bg, ushort bd) +{ + ushort cat = bd & ~(BDB | 0xff); /* mask out bold and data */ + if (bd & (BDL | BDA)) { + /* lines (light/double/heavy/arcs) */ + drawboxlines(x, y, w, h, fg, bd); + + } else if (cat == BBD) { + /* lower (8-X)/8 block */ + int d = DIV((uint8_t)bd * h, 8); + XftDrawRect(xd, fg, x, y + d, w, h - d); + + } else if (cat == BBU) { + /* upper X/8 block */ + XftDrawRect(xd, fg, x, y, w, DIV((uint8_t)bd * h, 8)); + + } else if (cat == BBL) { + /* left X/8 block */ + XftDrawRect(xd, fg, x, y, DIV((uint8_t)bd * w, 8), h); + + } else if (cat == BBR) { + /* right (8-X)/8 block */ + int d = DIV((uint8_t)bd * w, 8); + XftDrawRect(xd, fg, x + d, y, w - d, h); + + } else if (cat == BBQ) { + /* Quadrants */ + int w2 = DIV(w, 2), h2 = DIV(h, 2); + if (bd & TL) + XftDrawRect(xd, fg, x, y, w2, h2); + if (bd & TR) + XftDrawRect(xd, fg, x + w2, y, w - w2, h2); + if (bd & BL) + XftDrawRect(xd, fg, x, y + h2, w2, h - h2); + if (bd & BR) + XftDrawRect(xd, fg, x + w2, y + h2, w - w2, h - h2); + + } else if (bd & BBS) { + /* Shades - data is 1/2/3 for 25%/50%/75% alpha, respectively */ + int d = (uint8_t)bd; + XftColor xfc; + XRenderColor xrc = { .alpha = 0xffff }; + + xrc.red = DIV(fg->color.red * d + bg->color.red * (4 - d), 4); + xrc.green = DIV(fg->color.green * d + bg->color.green * (4 - d), 4); + xrc.blue = DIV(fg->color.blue * d + bg->color.blue * (4 - d), 4); + + XftColorAllocValue(xdpy, xvis, xcmap, &xrc, &xfc); + XftDrawRect(xd, &xfc, x, y, w, h); + XftColorFree(xdpy, xvis, xcmap, &xfc); + + } else if (cat == BRL) { + /* braille, each data bit corresponds to one dot at 2x4 grid */ + int w1 = DIV(w, 2); + int h1 = DIV(h, 4), h2 = DIV(h, 2), h3 = DIV(3 * h, 4); + + if (bd & 1) XftDrawRect(xd, fg, x, y, w1, h1); + if (bd & 2) XftDrawRect(xd, fg, x, y + h1, w1, h2 - h1); + if (bd & 4) XftDrawRect(xd, fg, x, y + h2, w1, h3 - h2); + if (bd & 8) XftDrawRect(xd, fg, x + w1, y, w - w1, h1); + if (bd & 16) XftDrawRect(xd, fg, x + w1, y + h1, w - w1, h2 - h1); + if (bd & 32) XftDrawRect(xd, fg, x + w1, y + h2, w - w1, h3 - h2); + if (bd & 64) XftDrawRect(xd, fg, x, y + h3, w1, h - h3); + if (bd & 128) XftDrawRect(xd, fg, x + w1, y + h3, w - w1, h - h3); + + } +} + +void +drawboxlines(int x, int y, int w, int h, XftColor *fg, ushort bd) +{ + /* s: stem thickness. width/8 roughly matches underscore thickness. */ + /* We draw bold as 1.5 * normal-stem and at least 1px thicker. */ + /* doubles draw at least 3px, even when w or h < 3. bold needs 6px. */ + int mwh = MIN(w, h); + int base_s = MAX(1, DIV(mwh, 8)); + int bold = (bd & BDB) && mwh >= 6; /* possibly ignore boldness */ + int s = bold ? MAX(base_s + 1, DIV(3 * base_s, 2)) : base_s; + int w2 = DIV(w - s, 2), h2 = DIV(h - s, 2); + /* the s-by-s square (x + w2, y + h2, s, s) is the center texel. */ + /* The base length (per direction till edge) includes this square. */ + + int light = bd & (LL | LU | LR | LD); + int double_ = bd & (DL | DU | DR | DD); + + if (light) { + /* d: additional (negative) length to not-draw the center */ + /* texel - at arcs and avoid drawing inside (some) doubles */ + int arc = bd & BDA; + int multi_light = light & (light - 1); + int multi_double = double_ & (double_ - 1); + /* light crosses double only at DH+LV, DV+LH (ref. shapes) */ + int d = arc || (multi_double && !multi_light) ? -s : 0; + + if (bd & LL) + XftDrawRect(xd, fg, x, y + h2, w2 + s + d, s); + if (bd & LU) + XftDrawRect(xd, fg, x + w2, y, s, h2 + s + d); + if (bd & LR) + XftDrawRect(xd, fg, x + w2 - d, y + h2, w - w2 + d, s); + if (bd & LD) + XftDrawRect(xd, fg, x + w2, y + h2 - d, s, h - h2 + d); + } + + /* double lines - also align with light to form heavy when combined */ + if (double_) { + /* + * going clockwise, for each double-ray: p is additional length + * to the single-ray nearer to the previous direction, and n to + * the next. p and n adjust from the base length to lengths + * which consider other doubles - shorter to avoid intersections + * (p, n), or longer to draw the far-corner texel (n). + */ + int dl = bd & DL, du = bd & DU, dr = bd & DR, dd = bd & DD; + if (dl) { + int p = dd ? -s : 0, n = du ? -s : dd ? s : 0; + XftDrawRect(xd, fg, x, y + h2 + s, w2 + s + p, s); + XftDrawRect(xd, fg, x, y + h2 - s, w2 + s + n, s); + } + if (du) { + int p = dl ? -s : 0, n = dr ? -s : dl ? s : 0; + XftDrawRect(xd, fg, x + w2 - s, y, s, h2 + s + p); + XftDrawRect(xd, fg, x + w2 + s, y, s, h2 + s + n); + } + if (dr) { + int p = du ? -s : 0, n = dd ? -s : du ? s : 0; + XftDrawRect(xd, fg, x + w2 - p, y + h2 - s, w - w2 + p, s); + XftDrawRect(xd, fg, x + w2 - n, y + h2 + s, w - w2 + n, s); + } + if (dd) { + int p = dr ? -s : 0, n = dl ? -s : dr ? s : 0; + XftDrawRect(xd, fg, x + w2 + s, y + h2 - p, s, h - h2 + p); + XftDrawRect(xd, fg, x + w2 - s, y + h2 - n, s, h - h2 + n); + } + } +} diff --git a/boxdraw_data.h b/boxdraw_data.h new file mode 100644 index 0000000..7890500 --- /dev/null +++ b/boxdraw_data.h @@ -0,0 +1,214 @@ +/* + * Copyright 2018 Avi Halachmi (:avih) avihpit@yahoo.com https://github.com/avih + * MIT/X Consortium License + */ + +/* + * U+25XX codepoints data + * + * References: + * http://www.unicode.org/charts/PDF/U2500.pdf + * http://www.unicode.org/charts/PDF/U2580.pdf + * + * Test page: + * https://github.com/GNOME/vte/blob/master/doc/boxes.txt + */ + +/* Each shape is encoded as 16-bits. Higher bits are category, lower are data */ +/* Categories (mutually exclusive except BDB): */ +/* For convenience, BDL/BDA/BBS/BDB are 1 bit each, the rest are enums */ +#define BDL (1<<8) /* Box Draw Lines (light/double/heavy) */ +#define BDA (1<<9) /* Box Draw Arc (light) */ + +#define BBD (1<<10) /* Box Block Down (lower) X/8 */ +#define BBL (2<<10) /* Box Block Left X/8 */ +#define BBU (3<<10) /* Box Block Upper X/8 */ +#define BBR (4<<10) /* Box Block Right X/8 */ +#define BBQ (5<<10) /* Box Block Quadrants */ +#define BRL (6<<10) /* Box Braille (data is lower byte of U28XX) */ + +#define BBS (1<<14) /* Box Block Shades */ +#define BDB (1<<15) /* Box Draw is Bold */ + +/* (BDL/BDA) Light/Double/Heavy x Left/Up/Right/Down/Horizontal/Vertical */ +/* Heavy is light+double (literally drawing light+double align to form heavy) */ +#define LL (1<<0) +#define LU (1<<1) +#define LR (1<<2) +#define LD (1<<3) +#define LH (LL+LR) +#define LV (LU+LD) + +#define DL (1<<4) +#define DU (1<<5) +#define DR (1<<6) +#define DD (1<<7) +#define DH (DL+DR) +#define DV (DU+DD) + +#define HL (LL+DL) +#define HU (LU+DU) +#define HR (LR+DR) +#define HD (LD+DD) +#define HH (HL+HR) +#define HV (HU+HD) + +/* (BBQ) Quadrants Top/Bottom x Left/Right */ +#define TL (1<<0) +#define TR (1<<1) +#define BL (1<<2) +#define BR (1<<3) + +/* Data for U+2500 - U+259F except dashes/diagonals */ +static const unsigned short boxdata[256] = { + /* light lines */ + [0x00] = BDL + LH, /* light horizontal */ + [0x02] = BDL + LV, /* light vertical */ + [0x0c] = BDL + LD + LR, /* light down and right */ + [0x10] = BDL + LD + LL, /* light down and left */ + [0x14] = BDL + LU + LR, /* light up and right */ + [0x18] = BDL + LU + LL, /* light up and left */ + [0x1c] = BDL + LV + LR, /* light vertical and right */ + [0x24] = BDL + LV + LL, /* light vertical and left */ + [0x2c] = BDL + LH + LD, /* light horizontal and down */ + [0x34] = BDL + LH + LU, /* light horizontal and up */ + [0x3c] = BDL + LV + LH, /* light vertical and horizontal */ + [0x74] = BDL + LL, /* light left */ + [0x75] = BDL + LU, /* light up */ + [0x76] = BDL + LR, /* light right */ + [0x77] = BDL + LD, /* light down */ + + /* heavy [+light] lines */ + [0x01] = BDL + HH, + [0x03] = BDL + HV, + [0x0d] = BDL + HR + LD, + [0x0e] = BDL + HD + LR, + [0x0f] = BDL + HD + HR, + [0x11] = BDL + HL + LD, + [0x12] = BDL + HD + LL, + [0x13] = BDL + HD + HL, + [0x15] = BDL + HR + LU, + [0x16] = BDL + HU + LR, + [0x17] = BDL + HU + HR, + [0x19] = BDL + HL + LU, + [0x1a] = BDL + HU + LL, + [0x1b] = BDL + HU + HL, + [0x1d] = BDL + HR + LV, + [0x1e] = BDL + HU + LD + LR, + [0x1f] = BDL + HD + LR + LU, + [0x20] = BDL + HV + LR, + [0x21] = BDL + HU + HR + LD, + [0x22] = BDL + HD + HR + LU, + [0x23] = BDL + HV + HR, + [0x25] = BDL + HL + LV, + [0x26] = BDL + HU + LD + LL, + [0x27] = BDL + HD + LU + LL, + [0x28] = BDL + HV + LL, + [0x29] = BDL + HU + HL + LD, + [0x2a] = BDL + HD + HL + LU, + [0x2b] = BDL + HV + HL, + [0x2d] = BDL + HL + LD + LR, + [0x2e] = BDL + HR + LL + LD, + [0x2f] = BDL + HH + LD, + [0x30] = BDL + HD + LH, + [0x31] = BDL + HD + HL + LR, + [0x32] = BDL + HR + HD + LL, + [0x33] = BDL + HH + HD, + [0x35] = BDL + HL + LU + LR, + [0x36] = BDL + HR + LU + LL, + [0x37] = BDL + HH + LU, + [0x38] = BDL + HU + LH, + [0x39] = BDL + HU + HL + LR, + [0x3a] = BDL + HU + HR + LL, + [0x3b] = BDL + HH + HU, + [0x3d] = BDL + HL + LV + LR, + [0x3e] = BDL + HR + LV + LL, + [0x3f] = BDL + HH + LV, + [0x40] = BDL + HU + LH + LD, + [0x41] = BDL + HD + LH + LU, + [0x42] = BDL + HV + LH, + [0x43] = BDL + HU + HL + LD + LR, + [0x44] = BDL + HU + HR + LD + LL, + [0x45] = BDL + HD + HL + LU + LR, + [0x46] = BDL + HD + HR + LU + LL, + [0x47] = BDL + HH + HU + LD, + [0x48] = BDL + HH + HD + LU, + [0x49] = BDL + HV + HL + LR, + [0x4a] = BDL + HV + HR + LL, + [0x4b] = BDL + HV + HH, + [0x78] = BDL + HL, + [0x79] = BDL + HU, + [0x7a] = BDL + HR, + [0x7b] = BDL + HD, + [0x7c] = BDL + HR + LL, + [0x7d] = BDL + HD + LU, + [0x7e] = BDL + HL + LR, + [0x7f] = BDL + HU + LD, + + /* double [+light] lines */ + [0x50] = BDL + DH, + [0x51] = BDL + DV, + [0x52] = BDL + DR + LD, + [0x53] = BDL + DD + LR, + [0x54] = BDL + DR + DD, + [0x55] = BDL + DL + LD, + [0x56] = BDL + DD + LL, + [0x57] = BDL + DL + DD, + [0x58] = BDL + DR + LU, + [0x59] = BDL + DU + LR, + [0x5a] = BDL + DU + DR, + [0x5b] = BDL + DL + LU, + [0x5c] = BDL + DU + LL, + [0x5d] = BDL + DL + DU, + [0x5e] = BDL + DR + LV, + [0x5f] = BDL + DV + LR, + [0x60] = BDL + DV + DR, + [0x61] = BDL + DL + LV, + [0x62] = BDL + DV + LL, + [0x63] = BDL + DV + DL, + [0x64] = BDL + DH + LD, + [0x65] = BDL + DD + LH, + [0x66] = BDL + DD + DH, + [0x67] = BDL + DH + LU, + [0x68] = BDL + DU + LH, + [0x69] = BDL + DH + DU, + [0x6a] = BDL + DH + LV, + [0x6b] = BDL + DV + LH, + [0x6c] = BDL + DH + DV, + + /* (light) arcs */ + [0x6d] = BDA + LD + LR, + [0x6e] = BDA + LD + LL, + [0x6f] = BDA + LU + LL, + [0x70] = BDA + LU + LR, + + /* Lower (Down) X/8 block (data is 8 - X) */ + [0x81] = BBD + 7, [0x82] = BBD + 6, [0x83] = BBD + 5, [0x84] = BBD + 4, + [0x85] = BBD + 3, [0x86] = BBD + 2, [0x87] = BBD + 1, [0x88] = BBD + 0, + + /* Left X/8 block (data is X) */ + [0x89] = BBL + 7, [0x8a] = BBL + 6, [0x8b] = BBL + 5, [0x8c] = BBL + 4, + [0x8d] = BBL + 3, [0x8e] = BBL + 2, [0x8f] = BBL + 1, + + /* upper 1/2 (4/8), 1/8 block (X), right 1/2, 1/8 block (8-X) */ + [0x80] = BBU + 4, [0x94] = BBU + 1, + [0x90] = BBR + 4, [0x95] = BBR + 7, + + /* Quadrants */ + [0x96] = BBQ + BL, + [0x97] = BBQ + BR, + [0x98] = BBQ + TL, + [0x99] = BBQ + TL + BL + BR, + [0x9a] = BBQ + TL + BR, + [0x9b] = BBQ + TL + TR + BL, + [0x9c] = BBQ + TL + TR + BR, + [0x9d] = BBQ + TR, + [0x9e] = BBQ + BL + TR, + [0x9f] = BBQ + BL + TR + BR, + + /* Shades, data is an alpha value in 25% units (1/4, 1/2, 3/4) */ + [0x91] = BBS + 1, [0x92] = BBS + 2, [0x93] = BBS + 3, + + /* U+2504 - U+250B, U+254C - U+254F: unsupported (dashes) */ + /* U+2571 - U+2573: unsupported (diagonals) */ +}; diff --git a/config.def.h b/config.def.h index 0e01717..e3654a9 100644 --- a/config.def.h +++ b/config.def.h @@ -56,6 +56,18 @@ static unsigned int blinktimeout = 800; */ static unsigned int cursorthickness = 2; +/* + * 1: render most of the lines/blocks characters without using the font for + * perfect alignment between cells (U2500 - U259F except dashes/diagonals). + * Bold affects lines thickness if boxdraw_bold is not 0. Italic is ignored. + * 0: disable (render all U25XX glyphs normally from the font). + */ +const int boxdraw = 0; +const int boxdraw_bold = 0; + +/* braille (U28XX): 1: render as adjacent "pixels", 0: use font */ +const int boxdraw_braille = 0; + /* * bell volume. It must be a value between -100 and 100. Use 0 for disabling * it diff --git a/st.c b/st.c index b8e6077..d65f722 100644 --- a/st.c +++ b/st.c @@ -1230,6 +1230,9 @@ tsetchar(Rune u, Glyph *attr, int x, int y) term.dirty[y] = 1; term.line[y][x] = *attr; term.line[y][x].u = u; + + if (isboxdraw(u)) + term.line[y][x].mode |= ATTR_BOXDRAW; } void diff --git a/st.h b/st.h index 38c61c4..9275632 100644 --- a/st.h +++ b/st.h @@ -33,6 +33,7 @@ enum glyph_attribute { ATTR_WRAP = 1 << 8, ATTR_WIDE = 1 << 9, ATTR_WDUMMY = 1 << 10, + ATTR_BOXDRAW = 1 << 11, ATTR_BOLD_FAINT = ATTR_BOLD | ATTR_FAINT, }; @@ -110,6 +111,14 @@ void *xmalloc(size_t); void *xrealloc(void *, size_t); char *xstrdup(char *); +int isboxdraw(Rune); +ushort boxdrawindex(const Glyph *); +#ifdef XFT_VERSION +/* only exposed to x.c, otherwise we'll need Xft.h for the types */ +void boxdraw_xinit(Display *, Colormap, XftDraw *, Visual *); +void drawboxes(int, int, int, int, XftColor *, XftColor *, const XftGlyphFontSpec *, int); +#endif + /* config.h globals */ extern char *utmp; extern char *stty_args; @@ -120,3 +129,4 @@ extern char *termname; extern unsigned int tabspaces; extern unsigned int defaultfg; extern unsigned int defaultbg; +extern const int boxdraw, boxdraw_bold, boxdraw_braille; diff --git a/x.c b/x.c index 0422421..c740bed 100644 --- a/x.c +++ b/x.c @@ -1118,6 +1118,8 @@ xinit(int cols, int rows) xsel.xtarget = XInternAtom(xw.dpy, "UTF8_STRING", 0); if (xsel.xtarget == None) xsel.xtarget = XA_STRING; + + boxdraw_xinit(xw.dpy, xw.cmap, xw.draw, xw.vis); } int @@ -1164,8 +1166,13 @@ xmakeglyphfontspecs(XftGlyphFontSpec *specs, const Glyph *glyphs, int len, int x yp = winy + font->ascent; } - /* Lookup character index with default font. */ - glyphidx = XftCharIndex(xw.dpy, font->match, rune); + if (mode & ATTR_BOXDRAW) { + /* minor shoehorning: boxdraw uses only this ushort */ + glyphidx = boxdrawindex(&glyphs[i]); + } else { + /* Lookup character index with default font. */ + glyphidx = XftCharIndex(xw.dpy, font->match, rune); + } if (glyphidx) { specs[numspecs].font = font->match; specs[numspecs].glyph = glyphidx; @@ -1372,8 +1379,12 @@ xdrawglyphfontspecs(const XftGlyphFontSpec *specs, Glyph base, int len, int x, i r.width = width; XftDrawSetClipRectangles(xw.draw, winx, winy, &r, 1); - /* Render the glyphs. */ - XftDrawGlyphFontSpec(xw.draw, fg, specs, len); + if (base.mode & ATTR_BOXDRAW) { + drawboxes(winx, winy, width / len, win.ch, fg, bg, specs, len); + } else { + /* Render the glyphs. */ + XftDrawGlyphFontSpec(xw.draw, fg, specs, len); + } /* Render underline and strikethrough. */ if (base.mode & ATTR_UNDERLINE) { @@ -1416,7 +1427,7 @@ xdrawcursor(int cx, int cy, Glyph g, int ox, int oy, Glyph og) /* * Select the right color for the right mode. */ - g.mode &= ATTR_BOLD|ATTR_ITALIC|ATTR_UNDERLINE|ATTR_STRUCK|ATTR_WIDE; + g.mode &= ATTR_BOLD|ATTR_ITALIC|ATTR_UNDERLINE|ATTR_STRUCK|ATTR_WIDE|ATTR_BOXDRAW; if (IS_SET(MODE_REVERSE)) { g.mode |= ATTR_REVERSE; -- 2.17.1