nx_viz_shape.nx source

1// nx_viz_shape.nx -- the SHAPES layer of the sovereign Nishi viz library (the d3-shape + d3-path equivalent, 2// bits-up). Generates SVG path strings from data points: line + area (the basis of line/area charts). Composes 3// with nx_viz_scale (scale data -> pixel coords, then shape -> path). No d3.js. Arc/pie await the trig layer. 4// Closes shape-line-area + path-serialize in viz_capability_target.tsv. Arc/pie via nx_viz_trig. license_tier: ORIGINAL 5import "nx_syscalls.nx" 6import "nx_viz_trig.nx" 7const K_MAGIC_10000: i64 = 10000 8 9// append integer to out at off; returns new off. 10func vsh_n(out: *u8, off: i64, val: i64) -> i64 { 11 var o: i64 = off 12 var v: i64 = val 13 if v < 0 { out[o] = 45 as u8; o = o + 1; v = 0 - v } 14 let t: *u8 = sys_mmap(28); var k: i64 = 0 15 if v == 0 { t[0] = 48 as u8; k = 1 } 16 while v > 0 { t[k] = (48 + (v % 10)) as u8; v = v / 10; k = k + 1 } 17 var i: i64 = 0; while i < k { out[o] = t[k - 1 - i]; o = o + 1; i = i + 1 } 18 return o 19} 20func vsh_lit(out: *u8, off: i64, s: *u8) -> i64 { var o: i64 = off; var i: i64 = 0; while s[i] != (0 as u8) { out[o] = s[i]; o = o + 1; i = i + 1 } return o } 21 22// LINE path: "M x0 y0 L x1 y1 ..." -> out (null-terminated). returns length. (d3.line) 23func vs_line(xs: *i64, ys: *i64, n: i64, out: *u8) -> i64 { 24 if n <= 0 { out[0] = 0 as u8; return 0 } 25 var o: i64 = vsh_lit(out, 0, "M " as *u8) 26 o = vsh_n(out, o, xs[0]); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, ys[0]) 27 var i: i64 = 1 28 while i < n { 29 o = vsh_lit(out, o, " L " as *u8) 30 o = vsh_n(out, o, xs[i]); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, ys[i]) 31 i = i + 1 32 } 33 out[o] = 0 as u8 34 return o 35} 36// AREA path: line across the top, down to baseline, back, closed. (d3.area) 37func vs_area(xs: *i64, ys: *i64, n: i64, baseline: i64, out: *u8) -> i64 { 38 if n <= 0 { out[0] = 0 as u8; return 0 } 39 var o: i64 = vs_line(xs, ys, n, out) 40 o = vsh_lit(out, o, " L " as *u8); o = vsh_n(out, o, xs[n - 1]); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, baseline) 41 o = vsh_lit(out, o, " L " as *u8); o = vsh_n(out, o, xs[0]); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, baseline) 42 o = vsh_lit(out, o, " Z" as *u8) 43 out[o] = 0 as u8 44 return o 45} 46// ARC/PIE slice: from center -> arc-start -> arc to arc-end -> close. SVG y is down (angles run clockwise). 47// x = cx + r*cos(a)/10000, y = cy + r*sin(a)/10000 (via nx_viz_trig). (d3.arc / d3.pie) 48func vs_arc(cx: i64, cy: i64, r: i64, a0_deg: i64, a1_deg: i64, out: *u8) -> i64 { 49 let x0: i64 = cx + (r * vs_cos(a0_deg)) / K_MAGIC_10000 50 let y0: i64 = cy + (r * vs_sin(a0_deg)) / K_MAGIC_10000 51 let x1: i64 = cx + (r * vs_cos(a1_deg)) / K_MAGIC_10000 52 let y1: i64 = cy + (r * vs_sin(a1_deg)) / K_MAGIC_10000 53 var large: i64 = 0 54 if (a1_deg - a0_deg) > 180 { large = 1 } 55 var o: i64 = vsh_lit(out, 0, "M " as *u8) 56 o = vsh_n(out, o, cx); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, cy) 57 o = vsh_lit(out, o, " L " as *u8); o = vsh_n(out, o, x0); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, y0) 58 o = vsh_lit(out, o, " A " as *u8); o = vsh_n(out, o, r); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, r) 59 o = vsh_lit(out, o, " 0 " as *u8); o = vsh_n(out, o, large); o = vsh_lit(out, o, " 1 " as *u8) 60 o = vsh_n(out, o, x1); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, y1) 61 o = vsh_lit(out, o, " Z" as *u8) 62 out[o] = 0 as u8 63 return o 64} 65// SYMBOL marker path centred at (cx,cy), radius r. typ: 0=square 1=diamond 2=triangle. (d3.symbol) 66func vs_symbol(typ: i64, cx: i64, cy: i64, r: i64, out: *u8) -> i64 { 67 var o: i64 = 0 68 if typ == 0 { 69 o = vsh_lit(out, 0, "M " as *u8); o = vsh_n(out, o, cx - r); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, cy - r) 70 o = vsh_lit(out, o, " L " as *u8); o = vsh_n(out, o, cx + r); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, cy - r) 71 o = vsh_lit(out, o, " L " as *u8); o = vsh_n(out, o, cx + r); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, cy + r) 72 o = vsh_lit(out, o, " L " as *u8); o = vsh_n(out, o, cx - r); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, cy + r) 73 o = vsh_lit(out, o, " Z" as *u8) 74 } 75 if typ == 1 { 76 o = vsh_lit(out, 0, "M " as *u8); o = vsh_n(out, o, cx); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, cy - r) 77 o = vsh_lit(out, o, " L " as *u8); o = vsh_n(out, o, cx + r); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, cy) 78 o = vsh_lit(out, o, " L " as *u8); o = vsh_n(out, o, cx); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, cy + r) 79 o = vsh_lit(out, o, " L " as *u8); o = vsh_n(out, o, cx - r); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, cy) 80 o = vsh_lit(out, o, " Z" as *u8) 81 } 82 if typ == 2 { 83 o = vsh_lit(out, 0, "M " as *u8); o = vsh_n(out, o, cx); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, cy - r) 84 o = vsh_lit(out, o, " L " as *u8); o = vsh_n(out, o, cx + r); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, cy + r) 85 o = vsh_lit(out, o, " L " as *u8); o = vsh_n(out, o, cx - r); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, cy + r) 86 o = vsh_lit(out, o, " Z" as *u8) 87 } 88 out[o] = 0 as u8 89 return o 90} 91// LINK path: smooth horizontal cubic-Bezier S-curve from (x0,y0) to (x1,y1). (d3.linkHorizontal) 92func vs_link(x0: i64, y0: i64, x1: i64, y1: i64, out: *u8) -> i64 { 93 let mx: i64 = (x0 + x1) / 2 94 var o: i64 = vsh_lit(out, 0, "M " as *u8); o = vsh_n(out, o, x0); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, y0) 95 o = vsh_lit(out, o, " C " as *u8); o = vsh_n(out, o, mx); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, y0) 96 o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, mx); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, y1) 97 o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, x1); o = vsh_lit(out, o, " " as *u8); o = vsh_n(out, o, y1) 98 out[o] = 0 as u8 99 return o 100} 101func main() -> i64 { return 0 }