add webui

hpgl_svg.py

@@ -0,0 +1,127 @@
+"""
+Convert a Program to SVG for browser display.
+No tkinter dependency; used by the web UI.
+"""
+from __future__ import division
+
+
+# Plotter units to mm (HP-GL typical: 1 unit = 0.025 mm)
+UNITS_PER_MM = 40.0
+
+# Space for X and Y rulers (labels in plotter units)
+RULER_LEFT = 52
+RULER_BOTTOM = 36
+MARGIN_TOP = 16
+MARGIN_RIGHT = 16
+
+
+def program_to_svg(program, width=800, height=600, margin=20, show_scale_bar=True):
+    """
+    Render Program to SVG string. Fits content into width x height.
+    Always draws X and Y rulers showing bounds (xmin, xmax, ymin, ymax) in plotter units.
+    HPGL Y is flipped so it displays top-down in SVG.
+    """
+    if not program.commands:
+        return _empty_svg(width, height)
+
+    w, h = program.winsize
+    if w == 0 or h == 0:
+        return _empty_svg(width, height)
+
+    xmin, ymin = program.xmin, program.ymin
+    xmax, ymax = program.xmax, program.ymax
+    vw = width - RULER_LEFT - MARGIN_RIGHT
+    vh = height - MARGIN_TOP - RULER_BOTTOM
+    scale = min(vw / w, vh / h)
+    cx, cy = program.center
+    ox = RULER_LEFT + vw / 2 - cx * scale
+    oy = MARGIN_TOP + vh / 2 + cy * scale  # flip Y: HPGL y up -> SVG y down
+
+    def tx(x):
+        return x * scale + ox
+
+    def ty(y):
+        return -y * scale + oy
+
+    path_segments = []
+    circles = []
+    x, y = None, None
+
+    for cmd in program.commands:
+        if cmd.name == 'PU':
+            x, y = cmd.x, cmd.y
+        elif cmd.name == 'PD':
+            if x is not None and y is not None:
+                path_segments.append('M {:.2f} {:.2f} L {:.2f} {:.2f}'.format(
+                    tx(x), ty(y), tx(cmd.x), ty(cmd.y)))
+            x, y = cmd.x, cmd.y
+        elif cmd.name == 'CI' and cmd.args:
+            r = abs(cmd.args[0]) * scale
+            cx_svg = tx(x) if x is not None else (RULER_LEFT + vw / 2)
+            cy_svg = ty(y) if y is not None else (MARGIN_TOP + vh / 2)
+            circles.append(
+                '<circle cx="{:.2f}" cy="{:.2f}" r="{:.2f}" fill="none" stroke="currentColor" stroke-width="1"/>'
+                .format(cx_svg, cy_svg, r))
+
+    parts = []
+    if path_segments:
+        path_d = ' '.join(path_segments)
+        parts.append('<path d="{}" fill="none" stroke="currentColor" stroke-width="1"/>'.format(path_d))
+    parts.extend(circles)
+
+    # X and Y rulers showing bounds (always)
+    parts.append(_rulers_svg(width, height, xmin, ymin, xmax, ymax, tx, ty))
+
+    return (
+        '<?xml version="1.0" encoding="UTF-8"?>\n'
+        '<svg xmlns="http://www.w3.org/2000/svg" '
+        'width="{w}" height="{h}" viewBox="0 0 {w} {h}">\n'
+        '<g>\n{body}\n</g>\n</svg>'
+    ).format(w=width, h=height, body='\n'.join(parts))
+
+
+def _rulers_svg(width, height, xmin, ymin, xmax, ymax, tx, ty):
+    """Draw X and Y rulers with bounds labels (plotter units)."""
+    # X ruler: bottom, from xmin to xmax
+    y_xruler = height - RULER_BOTTOM + 8
+    x0_x = tx(xmin)
+    x1_x = tx(xmax)
+    tick_y0 = y_xruler
+    tick_y1 = y_xruler + 6
+    # Y ruler: left, from ymin (bottom in SVG) to ymax (top in SVG)
+    x_yruler = RULER_LEFT - 24
+    y0_y = ty(ymin)  # bottom of drawing in SVG
+    y1_y = ty(ymax)  # top of drawing in SVG
+    tick_x0 = x_yruler + 18
+    tick_x1 = x_yruler + 24
+    font = 'font-size="11" font-family="system-ui,sans-serif" fill="#374151"'
+    return (
+        '<g stroke="#6b7280" fill="#374151" stroke-width="1">'
+        # X axis line and ticks
+        '<line x1="{x0_x:.1f}" y1="{y_xruler:.1f}" x2="{x1_x:.1f}" y2="{y_xruler:.1f}"/>'
+        '<line x1="{x0_x:.1f}" y1="{tick_y0:.1f}" x2="{x0_x:.1f}" y2="{tick_y1:.1f}"/>'
+        '<line x1="{x1_x:.1f}" y1="{tick_y0:.1f}" x2="{x1_x:.1f}" y2="{tick_y1:.1f}"/>'
+        '<text x="{x0_x:.1f}" y="{label_y:.1f}" text-anchor="middle" {font}>{xmin:.0f}</text>'
+        '<text x="{x1_x:.1f}" y="{label_y:.1f}" text-anchor="middle" {font}>{xmax:.0f}</text>'
+        # Y axis line and ticks
+        '<line x1="{x_yruler:.1f}" y1="{y0_y:.1f}" x2="{x_yruler:.1f}" y2="{y1_y:.1f}"/>'
+        '<line x1="{tick_x0:.1f}" y1="{y0_y:.1f}" x2="{tick_x1:.1f}" y2="{y0_y:.1f}"/>'
+        '<line x1="{tick_x0:.1f}" y1="{y1_y:.1f}" x2="{tick_x1:.1f}" y2="{y1_y:.1f}"/>'
+        '<text x="{y_label_x:.1f}" y="{y0_y:.1f}" text-anchor="end" dominant-baseline="middle" {font}>{ymin:.0f}</text>'
+        '<text x="{y_label_x:.1f}" y="{y1_y:.1f}" text-anchor="end" dominant-baseline="middle" {font}>{ymax:.0f}</text>'
+        '</g>'
+    ).format(
+        x0_x=x0_x, x1_x=x1_x, y_xruler=y_xruler, tick_y0=tick_y0, tick_y1=tick_y1,
+        label_y=y_xruler + 20, xmin=xmin, xmax=xmax,
+        x_yruler=x_yruler, y0_y=y0_y, y1_y=y1_y, tick_x0=tick_x0, tick_x1=tick_x1,
+        y_label_x=x_yruler + 14, ymin=ymin, ymax=ymax,
+        font=font
+    )
+
+
+def _empty_svg(width, height):
+    return (
+        '<?xml version="1.0" encoding="UTF-8"?>\n'
+        '<svg xmlns="http://www.w3.org/2000/svg" width="{w}" height="{h}" viewBox="0 0 {w} {h}">\n'
+        '<text x="{x}" y="{y}" fill="#999">No content</text>\n</svg>'
+    ).format(w=width, h=height, x=width // 2 - 30, y=height // 2)