ask the icon cache for the inline block icon

The three block-icon call sites each spelled out the same expression that
ItemIconCache::getInlineIcon() now is: the bare icon at the line's text
height, null when the file is missing. They call the helper instead, and
HeaderBar::blockIcon() -- which was that expression and nothing else --
is gone along with its stale "loaded once on first use" comment.

Each site still passes its own widget font, so nothing about the sizing
changes; the rule now lives in one place rather than four.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Ne3mejABZoLWKLh8fgpM3x

src/ui/BlueprintSelectionDialog.cpp

@@ -266,9 +266,7 @@ void BlueprintSelectionDialog::rebuildGrid()
 
     // Block icon shown to the right of each cost (REQ-UI-BLUEPRINT-CARD); null when no
     // building_block icon exists, in which case the cost is the bare number.
-    const QPixmap blockIcon = m_itemIcons->hasIcon(kBlockItemId)
+    const QPixmap blockIcon = m_itemIcons->getInlineIcon(kBlockItemId, font());
-        ? m_itemIcons->getPixmap(kBlockItemId, QFontMetrics(font()).height())
-        : QPixmap();
 
     const QSize cardSize = getCardSize(font());
 

src/ui/BuildButtonBar.cpp

@@ -175,9 +175,7 @@ BuildButtonBar::BuildButtonBar(Simulation* sim, const GameConfig* config,
 
     // Block icon shown to the right of each button's cost (REQ-UI-BUILD-COST); null
     // when no building_block icon exists, in which case the cost is the bare number.
-    const QPixmap blockIcon = m_itemIcons->hasIcon(kBlockItemId)
+    const QPixmap blockIcon = m_itemIcons->getInlineIcon(kBlockItemId, font());
-        ? m_itemIcons->getPixmap(kBlockItemId, QFontMetrics(font()).height())
-        : QPixmap();
 
     for (const BuildingDef& def : config->buildings.buildings)
     {

src/ui/HeaderBar.cpp

@@ -3,7 +3,6 @@
 #include <cmath>
 #include <string>
 
-#include <QFontMetrics>
 #include <QHBoxLayout>
 #include <QIcon>
 #include <QLabel>
@@ -120,19 +119,11 @@ void HeaderBar::handleEvent(std::shared_ptr<const ExpansionCostChangedEvent> /*e
     updateExpandButton();
 }
 
-QPixmap HeaderBar::blockIcon() const
-{
-    if (!m_itemIcons->hasIcon(kBlockItemId)) { return QPixmap(); }
-    // Sized to the header text height so it sits inline with the caption.
-    const int sizePx = QFontMetrics(font()).height();
-    return m_itemIcons->getPixmap(kBlockItemId, sizePx);
-}
-
 void HeaderBar::updateBlocksLabel()
 {
     const int blocks = m_sim->getBuildingBlocksStock();
 
-    const QPixmap icon = blockIcon();
+    const QPixmap icon = m_itemIcons->getInlineIcon(kBlockItemId, font());
     if (icon.isNull())
     {
         // Fallback text form when no building_block icon exists (REQ-UI-BLOCKS-ICON).
@@ -151,7 +142,7 @@ void HeaderBar::updateExpandButton()
 
     m_expandButton->setEnabled(blocks >= expansionCost);
 
-    const QPixmap icon = blockIcon();
+    const QPixmap icon = m_itemIcons->getInlineIcon(kBlockItemId, font());
     if (icon.isNull())
     {
         // Fallback text form when no building_block icon exists (REQ-UI-EXPAND-BUTTON).

src/ui/HeaderBar.h

@@ -61,10 +61,6 @@ private:
     // (REQ-UI-BLOCKS-ICON).
     void updateBlocksLabel();
 
-    // The building_block icon at the header's text height, or a null pixmap when no
-    // icon file exists. Loaded once via m_itemIcons on first use.
-    QPixmap blockIcon() const;
-
     QLabel*                  m_timeLabel;
     QLabel*                  m_blocksLabel;
     QLabel*                  m_artifactsLabel;