|
| 1 | +""" |
| 2 | +Color-key (legend) widgets for the peak-indexing visualization tabs. |
| 3 | +
|
| 4 | +Provides reference images for orientation color modes that produce |
| 5 | +per-point RGB values without a Plotly colorbar: |
| 6 | +
|
| 7 | +* ``cubic_ipf`` -> standard cubic IPF stereographic triangle with |
| 8 | + 001 (red) / 101 (green) / 111 (blue) corners. |
| 9 | +* ``pole_hsv`` (and pole-figure ``hsv_position``) -> circular HSV |
| 10 | + color wheel. |
| 11 | +
|
| 12 | +The pixel arrays are produced once at import time by |
| 13 | +:func:`laue_portal.analysis.coloring.make_cubic_ipf_triangle` and |
| 14 | +:func:`laue_portal.analysis.coloring.make_color_hexagon`, then encoded |
| 15 | +as base64 PNG data URIs that can be served directly via ``html.Img``. |
| 16 | +
|
| 17 | +The corner labels (001 / 101 / 111) and the dynamic caption |
| 18 | +("Crystal direction \u2225 sample normal", ...) are rendered as HTML |
| 19 | +elements layered around the image so they remain styleable via CSS |
| 20 | +without requiring PIL fonts. |
| 21 | +""" |
| 22 | + |
| 23 | +from __future__ import annotations |
| 24 | + |
| 25 | +import base64 |
| 26 | +import io |
| 27 | +from typing import Optional |
| 28 | + |
| 29 | +from dash import html |
| 30 | +from PIL import Image |
| 31 | + |
| 32 | +from laue_portal.analysis.coloring import ( |
| 33 | + make_color_hexagon, |
| 34 | + make_cubic_ipf_triangle, |
| 35 | +) |
| 36 | + |
| 37 | +# --------------------------------------------------------------------------- |
| 38 | +# Pre-rendered color-key images (computed once at import) |
| 39 | +# --------------------------------------------------------------------------- |
| 40 | + |
| 41 | + |
| 42 | +def _rgba_array_to_data_uri(rgba: "np.ndarray") -> str: # noqa: F821 |
| 43 | + """Encode an (H, W, 4) uint8 RGBA array as a base64 PNG data URI.""" |
| 44 | + img = Image.fromarray(rgba, mode="RGBA") |
| 45 | + buf = io.BytesIO() |
| 46 | + img.save(buf, format="PNG", optimize=True) |
| 47 | + encoded = base64.b64encode(buf.getvalue()).decode("ascii") |
| 48 | + return f"data:image/png;base64,{encoded}" |
| 49 | + |
| 50 | + |
| 51 | +# Generated lazily on first access so module import stays cheap; cached |
| 52 | +# afterwards. Resolutions chosen to render crisply in the ~200 px sidebar |
| 53 | +# slot (devices with 2x DPR render at 400 px). |
| 54 | +_IPF_TRIANGLE_RES = 256 |
| 55 | +_HSV_HEXAGON_RES = 256 |
| 56 | + |
| 57 | +_ipf_triangle_uri: Optional[str] = None |
| 58 | +_hsv_hexagon_uri: Optional[str] = None |
| 59 | + |
| 60 | + |
| 61 | +def _get_ipf_triangle_uri() -> str: |
| 62 | + global _ipf_triangle_uri |
| 63 | + if _ipf_triangle_uri is None: |
| 64 | + _ipf_triangle_uri = _rgba_array_to_data_uri(make_cubic_ipf_triangle(resolution=_IPF_TRIANGLE_RES)) |
| 65 | + return _ipf_triangle_uri |
| 66 | + |
| 67 | + |
| 68 | +def _get_hsv_hexagon_uri() -> str: |
| 69 | + global _hsv_hexagon_uri |
| 70 | + if _hsv_hexagon_uri is None: |
| 71 | + _hsv_hexagon_uri = _rgba_array_to_data_uri(make_color_hexagon(resolution=_HSV_HEXAGON_RES)) |
| 72 | + return _hsv_hexagon_uri |
| 73 | + |
| 74 | + |
| 75 | +# --------------------------------------------------------------------------- |
| 76 | +# Caption helpers |
| 77 | +# --------------------------------------------------------------------------- |
| 78 | + |
| 79 | +# Human-readable surface-direction labels matching the |
| 80 | +# ``orientation-surface-select`` / ``stereo-surface-select`` options. |
| 81 | +_SURFACE_LABELS = { |
| 82 | + "normal": "sample normal", |
| 83 | + "X": "sample X", |
| 84 | + "H": "sample H", |
| 85 | + "Y": "sample Y", |
| 86 | + "Z": "sample Z", |
| 87 | +} |
| 88 | + |
| 89 | + |
| 90 | +def _surface_label(surface: Optional[str]) -> str: |
| 91 | + if not surface: |
| 92 | + return "sample normal" |
| 93 | + return _SURFACE_LABELS.get(surface, f"sample {surface}") |
| 94 | + |
| 95 | + |
| 96 | +# --------------------------------------------------------------------------- |
| 97 | +# Public component builders |
| 98 | +# --------------------------------------------------------------------------- |
| 99 | + |
| 100 | + |
| 101 | +def ipf_triangle_legend(caption: Optional[str] = None) -> html.Div: |
| 102 | + """ |
| 103 | + Build the cubic IPF reference triangle widget. |
| 104 | +
|
| 105 | + Parameters |
| 106 | + ---------- |
| 107 | + caption |
| 108 | + Optional short text rendered below the triangle (e.g. |
| 109 | + ``"Crystal direction \u2225 sample normal"``). |
| 110 | + """ |
| 111 | + img = html.Img( |
| 112 | + src=_get_ipf_triangle_uri(), |
| 113 | + alt="Cubic IPF standard triangle", |
| 114 | + className="pi-ipf-legend-img", |
| 115 | + draggable="false", |
| 116 | + ) |
| 117 | + |
| 118 | + # Corner label positions are tuned to the geometry of |
| 119 | + # ``make_cubic_ipf_triangle``: the triangle occupies the lower-left |
| 120 | + # half of the square, with vertices at the bottom-left (001), the |
| 121 | + # right edge midpoint-ish (101), and the top-right (111). |
| 122 | + corners = [ |
| 123 | + html.Span("001", className="pi-ipf-corner-label pi-ipf-corner-001"), |
| 124 | + html.Span("101", className="pi-ipf-corner-label pi-ipf-corner-101"), |
| 125 | + html.Span("111", className="pi-ipf-corner-label pi-ipf-corner-111"), |
| 126 | + ] |
| 127 | + |
| 128 | + children = [ |
| 129 | + html.Div([img, *corners], className="pi-ipf-legend-frame"), |
| 130 | + ] |
| 131 | + if caption: |
| 132 | + children.append(html.Div(caption, className="pi-ipf-caption")) |
| 133 | + |
| 134 | + return html.Div(children, className="pi-ipf-legend") |
| 135 | + |
| 136 | + |
| 137 | +def hsv_hexagon_legend(caption: Optional[str] = None) -> html.Div: |
| 138 | + """ |
| 139 | + Build the HSV color-wheel reference widget for ``pole_hsv`` mode. |
| 140 | +
|
| 141 | + Six axis labels are layered around the circle (none on the vertical |
| 142 | + poles): +X right, -X left, +Y top-left, -Y bottom-right, +Z |
| 143 | + bottom-left, -Z top-right. Positioning is done via CSS classes so |
| 144 | + the labels remain styleable. |
| 145 | + """ |
| 146 | + img = html.Img( |
| 147 | + src=_get_hsv_hexagon_uri(), |
| 148 | + alt="HSV color wheel", |
| 149 | + className="pi-ipf-legend-img pi-ipf-legend-img--circle", |
| 150 | + draggable="false", |
| 151 | + ) |
| 152 | + axis_labels = [ |
| 153 | + html.Span("+X", className="pi-hsv-axis-label pi-hsv-axis-px"), |
| 154 | + html.Span("\u2212X", className="pi-hsv-axis-label pi-hsv-axis-nx"), |
| 155 | + html.Span("+Y", className="pi-hsv-axis-label pi-hsv-axis-py"), |
| 156 | + html.Span("\u2212Y", className="pi-hsv-axis-label pi-hsv-axis-ny"), |
| 157 | + html.Span("+Z", className="pi-hsv-axis-label pi-hsv-axis-pz"), |
| 158 | + html.Span("\u2212Z", className="pi-hsv-axis-label pi-hsv-axis-nz"), |
| 159 | + ] |
| 160 | + children = [html.Div([img, *axis_labels], className="pi-ipf-legend-frame")] |
| 161 | + if caption: |
| 162 | + children.append(html.Div(caption, className="pi-ipf-caption")) |
| 163 | + return html.Div(children, className="pi-ipf-legend") |
| 164 | + |
| 165 | + |
| 166 | +def _empty_key(text: str = "No reference key for this color mode.") -> html.Div: |
| 167 | + return html.Div( |
| 168 | + html.Small(text, className="text-muted"), |
| 169 | + className="pi-ipf-legend pi-ipf-legend--empty", |
| 170 | + ) |
| 171 | + |
| 172 | + |
| 173 | +# --------------------------------------------------------------------------- |
| 174 | +# Dispatchers used by page callbacks |
| 175 | +# --------------------------------------------------------------------------- |
| 176 | + |
| 177 | + |
| 178 | +def orientation_color_key(color_mode: Optional[str], surface: Optional[str]) -> html.Div: |
| 179 | + """ |
| 180 | + Return the appropriate color-key widget for the *Orientation* tab. |
| 181 | +
|
| 182 | + Parameters |
| 183 | + ---------- |
| 184 | + color_mode |
| 185 | + Value of ``orientation-color-select`` (e.g. ``"cubic_ipf"``). |
| 186 | + surface |
| 187 | + Value of ``orientation-surface-select`` (e.g. ``"normal"``). |
| 188 | + """ |
| 189 | + surf = _surface_label(surface) |
| 190 | + |
| 191 | + if color_mode == "cubic_ipf": |
| 192 | + return ipf_triangle_legend( |
| 193 | + caption=f"Crystal direction \u2225 {surf}", |
| 194 | + ) |
| 195 | + if color_mode == "pole_hsv": |
| 196 | + return hsv_hexagon_legend( |
| 197 | + caption=f"{surf.capitalize()} direction in stereographic HSV", |
| 198 | + ) |
| 199 | + return _empty_key() |
| 200 | + |
| 201 | + |
| 202 | +def stereo_color_key(color_mode: Optional[str]) -> html.Div: |
| 203 | + """ |
| 204 | + Return the appropriate color-key widget for the *Pole Figure* tab. |
| 205 | +
|
| 206 | + The pole-figure tab has its own surface selector but the legend on |
| 207 | + this tab represents the cubic fundamental zone itself, so the caption |
| 208 | + stays static. |
| 209 | + """ |
| 210 | + if color_mode == "ipf": |
| 211 | + return ipf_triangle_legend(caption="Cubic IPF (m\u20133m)") |
| 212 | + if color_mode == "hsv_position": |
| 213 | + return hsv_hexagon_legend(caption="Stereographic position (HSV)") |
| 214 | + return _empty_key() |
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