fix(qt): blend the industrial rows in and decline unbounded ranges

MetaUI/qt/include/meta_qt/designs/industrial/slider_chrome.hpp

@@ -2,6 +2,8 @@
    Public License. The full license is in the file LICENSE, distributed with
    this software. */
 #pragma once
+#include <limits>
+
 #include <QPainterPath>
 #include <QRect>
 #include <QString>
@@ -56,6 +58,34 @@ void paint_slider_row(QPainter             &painter,
                       int                   height);
 
 /// Stylesheet for the value field, following the theme and row state.
+/** @brief True when a rail can meaningfully represent the range [lo, hi].
+ *
+ * A bound of FLT_MAX or INT_MAX does not mean "a very wide slider", it means
+ * "no limit". A rail a couple of hundred pixels wide cannot show that: every
+ * value a user would type lands in the first pixel, and a drag moves the value
+ * by astronomical steps. That is the broken behaviour on the unbounded rows.
+ *
+ * Declining them here lets them fall through to stock, whose SliderFloat has a
+ * proper unbounded mode: the handle sits centred at rest and drags relatively
+ * instead of mapping to an absolute position. Using the fallback chain is the
+ * point of the design registry, so this belongs in can_render() rather than as
+ * a special case inside the paint code.
+ *
+ * The sentinel test deliberately matches stock's `is_range_bounded()` exactly,
+ * against the type's own limits. A looser threshold would leave a gap where a
+ * merely huge range is declined here but still counted as bounded there, which
+ * breaks it in both designs rather than neither.
+ */
+template <typename T> bool has_usable_range(T lo, T hi)
+{
+  // Written as a positive test so a NaN bound falls out here rather than
+  // passing an inverted comparison.
+  if (!(hi > lo)) return false;
+
+  return lo > std::numeric_limits<T>::lowest() &&
+         hi < std::numeric_limits<T>::max();
+}
+
 QString field_stylesheet(const Theme &theme,
                          bool         editing,
                          bool         modified,

MetaUI/qt/include/meta_qt/ui/theme.hpp

@@ -25,6 +25,21 @@ QFont mono_font(int pixel_size);
 /// The UI sans face. No family override -- the system font is correct here.
 QFont ui_font(int pixel_size, bool bold = false, qreal letter_spacing = 0.0);
 
+/** @brief Font for an attribute row's label.
+ *
+ * The host application's font, at the row size. Deliberately not a probed
+ * family, not letter-spaced and not uppercased.
+ *
+ * The design originally set all three, which made a panel of parameter names
+ * read as its own separate piece of UI sitting next to the rest of the
+ * application rather than part of it. Attribute keys are words the user reads,
+ * not chrome, and uppercasing them costs legibility for styling.
+ *
+ * Defined once because five row types were each setting the same two lines,
+ * which is five places for them to drift apart.
+ */
+QFont row_label_font();
+
 /** @brief Geometry and timing constants for a design.
  *
  * Separate from the palette because a colourway swap changes colours only,

MetaUI/qt/src/designs/industrial/check_row.cpp

@@ -71,8 +71,7 @@ void CheckRow::paintEvent(QPaintEvent *)
   const bool     locked = is_locked();
 
   // --- label
-  QFont label_font = ui_font(12, false, 1.0);
-  label_font.setCapitalization(QFont::AllUppercase);
+  QFont label_font = row_label_font();
   painter.setFont(label_font);
   painter.setPen(t.state_ink(is_modified(), locked));
   const int label_w = width() - m.switch_width - m.gap;

MetaUI/qt/src/designs/industrial/combo.cpp

@@ -260,8 +260,7 @@ void paint_combo_field(QWidget       &widget,
                         m.label_min_width,
                         m.label_max_width));
 
-  QFont label_font = ui_font(12, false, 1.0);
-  label_font.setCapitalization(QFont::AllUppercase);
+  QFont label_font = row_label_font();
   painter.setFont(label_font);
   painter.setPen(theme.state_ink(modified, locked));
   painter.drawText(QRect(0, 0, label_width, height),

MetaUI/qt/src/designs/industrial/int_slider.cpp

@@ -95,7 +95,9 @@ bool IntSlider::can_render(const Attribute<int> &attr)
       !metadata.find(meta::keys::constraints::max))
     return false;
 
-  return meta::common::max(attr) > meta::common::min(attr);
+  // Declines unbounded ranges so they fall through to the stock input, which is
+  // the right control for a number with no limits.
+  return has_usable_range(meta::common::min(attr), meta::common::max(attr));
 }
 
 void IntSlider::set(const int &value)
@@ -140,8 +142,7 @@ void IntSlider::paintEvent(QPaintEvent *)
   visual.modified = is_modified();
   visual.locked = is_locked();
 
-  QFont label_font = ui_font(12, false, 1.0);
-  label_font.setCapitalization(QFont::AllUppercase);
+  QFont label_font = row_label_font();
   visual.label = elide_label(QString::fromStdString(label_),
                              label_font,
                              geometry.label.width());

MetaUI/qt/src/designs/industrial/param_slider.cpp

@@ -114,7 +114,9 @@ bool ParamSlider::can_render(const Attribute<float> &attr)
       !metadata.find(meta::keys::constraints::max))
     return false;
 
-  return meta::common::max(attr) > meta::common::min(attr);
+  // Declines unbounded ranges so they fall through to the stock input, which is
+  // the right control for a number with no limits.
+  return has_usable_range(meta::common::min(attr), meta::common::max(attr));
 }
 
 void ParamSlider::set(const float &value)
@@ -183,8 +185,7 @@ void ParamSlider::paintEvent(QPaintEvent *)
   visual.modified = is_modified();
   visual.locked = is_locked();
 
-  QFont label_font = ui_font(12, false, 1.0);
-  label_font.setCapitalization(QFont::AllUppercase);
+  QFont label_font = row_label_font();
   visual.label = elide_label(QString::fromStdString(label_),
                              label_font,
                              geometry.label.width());

MetaUI/qt/src/designs/industrial/slider_chrome.cpp

@@ -72,8 +72,7 @@ void paint_slider_row(QPainter             &painter,
   const Metrics &m = theme.metrics;
 
   // --- label. Text is the only thing state is allowed to change.
-  QFont label_font = ui_font(12, false, 1.0);
-  label_font.setCapitalization(QFont::AllUppercase);
+  QFont label_font = row_label_font();
   painter.setFont(label_font);
   painter.setPen(theme.state_ink(visual.modified, visual.locked));
   painter.drawText(geometry.label,

MetaUI/qt/src/ui/theme.cpp

@@ -70,6 +70,16 @@ QFont ui_font(int pixel_size, bool bold, qreal letter_spacing)
   return font;
 }
 
+QFont row_label_font()
+{
+  // QApplication::font() rather than ui_font(): the point is to match whatever
+  // the host is using, so the panel blends into the application instead of
+  // announcing itself.
+  QFont font = QApplication::font();
+  font.setPixelSize(12);
+  return font;
+}
+
 // --- Theme
 
 namespace
@@ -108,9 +118,14 @@ Theme Theme::from_palette(const QPalette &palette, const std::string &name)
   // --- surfaces
   t.page = window;
   t.bar = sink(window, 0.06);
-  // Deliberately a clear step off the page, not a hint of one. A card that is
-  // barely lighter than its background does not group anything.
-  t.section_surface = lift(window, 0.30);
+  // A clear step off the page, but only just. At a 0.30 lift the cards read as
+  // a separate piece of UI laid on top of the application rather than part of
+  // it, which is the main thing that made the panel stand out.
+  //
+  // 0.15 is roughly one step, and on a host whose window is #2B2B2B it lands on
+  // #4B4B4B, the same value such applications typically use for their secondary
+  // surface. Derived rather than hardcoded, so it still tracks the palette.
+  t.section_surface = lift(window, 0.15);
 
   // The header shares the card surface so a section reads as one block rather
   // than a bar with a differently coloured body under it. Hover and press are