st-patches/st-boxdraw.patch

517 lines
16 KiB
Diff

From 1630b7016d26c266d004f38ecfef2c4b708aa9a6 Mon Sep 17 00:00:00 2001
From: "Avi Halachmi (:avih)" <avihpit@yahoo.com>
Date: Fri, 26 Oct 2018 13:11:20 +0300
Subject: [PATCH] boxdraw: custom-draw U+25XX lines/blocks to align seamlessly
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 an option to custom-draw (without using the font)
most of the lines/blocks codepoints such that they're rendered
identically (per size) and align perfectly regardless of font, size
or chscale/cwscale configuration values.
138 shapes are supported (U+2500 - U+259F except dashes, diagonals
and shades), composited as 16-bit values at boxdraw_data.h .
See links and references at boxdraw_data.h
---
Makefile | 3 +-
boxdraw.c | 141 ++++++++++++++++++++++++++++++++++
boxdraw_data.h | 202 +++++++++++++++++++++++++++++++++++++++++++++++++
config.def.h | 8 ++
st.c | 3 +
st.h | 9 +++
x.c | 19 +++--
7 files changed, 379 insertions(+), 6 deletions(-)
create mode 100644 boxdraw.c
create mode 100644 boxdraw_data.h
diff --git a/Makefile b/Makefile
index 0b3cecd..8d3af33 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 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..357250f
--- /dev/null
+++ b/boxdraw.c
@@ -0,0 +1,141 @@
+#include <X11/Xft/Xft.h>
+#include "st.h"
+#include "boxdraw_data.h"
+
+static void drawbox(XftDraw *, int, int, int, int, XftColor *, ushort);
+static void drawboxlines(XftDraw *, int, int, int, int, XftColor *, ushort);
+
+/* public API */
+
+int
+isboxdraw(const Glyph *g)
+{
+ return (g->u & ~0xff) == 0x2500 &&
+ boxdata[(uint8_t)g->u] != 0 &&
+ (g->mode & ATTR_ITALIC) == 0;
+}
+
+/* the "index" is actually the entire shape data encoded as ushort */
+ushort
+boxdrawindex(const Glyph *g)
+{
+ return boxdata[(uint8_t)g->u] | ((g->mode & ATTR_BOLD) ? BDB : 0);
+}
+
+void
+drawboxes(XftDraw *xd, int x, int y, int cw, int ch, XftColor *fg,
+ const XftGlyphFontSpec *specs, int len)
+{
+ for ( ; len-- > 0; x += cw, specs++)
+ drawbox(xd, x, y, cw, ch, fg, (ushort)specs->glyph);
+}
+
+/* implementation */
+
+void
+drawbox(XftDraw *xd, int x, int y, int w, int h, XftColor *fg, ushort bd)
+{
+ if (bd & (BDL | BDA)) {
+ /* lines (light/double/heavy/arcs) */
+ drawboxlines(xd, x, y, w, h, fg, bd);
+
+ } else if (bd & BBD) {
+ /* lower (8-X)/8 block */
+ int d = ((uint8_t)bd * h + 4) / 8;
+ XftDrawRect(xd, fg, x, y + d, w, h - d);
+
+ } else if (bd & BBU) {
+ /* upper X/8 block */
+ XftDrawRect(xd, fg, x, y, w, ((uint8_t)bd * h + 4) / 8);
+
+ } else if (bd & BBL) {
+ /* left X/8 block */
+ XftDrawRect(xd, fg, x, y, ((uint8_t)bd * w + 4) / 8, h);
+
+ } else if (bd & BBR) {
+ /* right (8-X)/8 block */
+ int d = ((uint8_t)bd * w + 4) / 8;
+ XftDrawRect(xd, fg, x + d, y, w - d, h);
+
+ } else if (bd & BBQ) {
+ /* Quadrants */
+ int w2 = (w + 1) / 2, h2 = (h + 1) / 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);
+ }
+}
+
+void
+drawboxlines(XftDraw *xd, 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, (mwh + 4) / 8);
+ int bold = (bd & BDB) && mwh >= 6; /* possibly ignore boldness */
+ int s = bold ? MAX(base_s + 1, (3 * base_s + 1) / 2) : base_s;
+ int w2 = (w - s + 1) / 2, h2 = (h - s + 1) / 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..ee78cdc
--- /dev/null
+++ b/boxdraw_data.h
@@ -0,0 +1,202 @@
+/*
+ * 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): */
+#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 (1<<11) /* Box Block Left X/8 */
+#define BBU (1<<12) /* Box Block Upper X/8 */
+#define BBR (1<<13) /* Box Block Right X/8 */
+#define BBQ (1<<14) /* Box Block Quadrants */
+#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)
+
+/* 138 shapes are supported: U+2500 - U+259F except dashes/diagonals/shades */
+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,
+
+ /* U+2504 - U+250B, U+254C - U+254F: unsupported (dashes) */
+ /* U+2571 - U+2573: unsupported (diagonals) */
+ /* U+2591 - U+2593: unsupported (shades) */
+};
diff --git a/config.def.h b/config.def.h
index 823e79f..018cbe4 100644
--- a/config.def.h
+++ b/config.def.h
@@ -56,6 +56,14 @@ static unsigned int blinktimeout = 800;
*/
static unsigned int cursorthickness = 2;
+/*
+ * 1: custom-draw (without using the font) most of the lines/blocks characters
+ * for gapless alignment between cells. This includes all the codepoints at
+ * U+2500 - U+259F except dashes, diagonals and shades.
+ * 0: disable (render all glyphs normally from the font).
+ */
+const int boxdraw = 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 46cf2da..7ee136a 100644
--- a/st.c
+++ b/st.c
@@ -1228,6 +1228,9 @@ 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 (boxdraw && isboxdraw(&term.line[y][x]))
+ term.line[y][x].mode |= ATTR_BOXDRAW;
}
void
diff --git a/st.h b/st.h
index 38c61c4..fc68c3b 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 +111,13 @@ void *xmalloc(size_t);
void *xrealloc(void *, size_t);
char *xstrdup(char *);
+int isboxdraw(const Glyph *);
+ushort boxdrawindex(const Glyph *);
+#ifdef XFT_VERSION
+/* only exposed to x.c, otherwise we'll need Xft.h for the types */
+void drawboxes(XftDraw *, int, int, int, int, XftColor *, const XftGlyphFontSpec *, int);
+#endif
+
/* config.h globals */
extern char *utmp;
extern char *stty_args;
@@ -120,3 +128,4 @@ extern char *termname;
extern unsigned int tabspaces;
extern unsigned int defaultfg;
extern unsigned int defaultbg;
+extern const int boxdraw;
diff --git a/x.c b/x.c
index 00cb6b1..730f525 100644
--- a/x.c
+++ b/x.c
@@ -1164,8 +1164,13 @@ 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 +1377,12 @@ 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(xw.draw, winx, winy, width / len, win.ch, fg, specs, len);
+ } else {
+ /* Render the glyphs. */
+ XftDrawGlyphFontSpec(xw.draw, fg, specs, len);
+ }
/* Render underline and strikethrough. */
if (base.mode & ATTR_UNDERLINE) {
@@ -1416,7 +1425,7 @@ 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;
--
2.19.1