Update worldmap.cc

Currently, cities are not drawn until at least half of it is onscreen, meaning they "pop in" suddenly.  This fixes that problem.

Also, the check for city name was too aggressive, meaning the name of small cities (e.g. Motel in Sonora) would fail to render near the bottom of the screen.

src/worldmap.cc

@@ -534,7 +534,7 @@ static int wmTileGrabArt(int tileIdx);
 static int wmInterfaceRefresh();
 static void wmInterfaceRefreshDate(bool shouldRefreshWindow);
 static int wmMatchWorldPosToArea(int x, int y, int* areaIdxPtr);
-static int wmInterfaceDrawCircleOverlay(CityInfo* cityInfo, CitySizeDescription* citySizeInfo, unsigned char* buffer, int x, int y);
+static int wmInterfaceDrawCircleOverlay(CityInfo* cityInfo, CitySizeDescription* citySizeInfo, unsigned char* buffer, int x, int y, int destPitch);
 static void wmInterfaceDrawSubTileRectFogged(unsigned char* dest, int width, int height, int pitch);
 static int wmInterfaceDrawSubTileList(TileInfo* tileInfo, int column, int row, int x, int y, int a6);
 static int wmDrawCursorStopped();
@@ -5221,17 +5221,50 @@ static int wmInterfaceRefresh()
     }
 
     // Render cities.
-    for (int index = 0; index < wmMaxAreaNum; index++) {
-        CityInfo* cityInfo = &(wmAreaInfoList[index]);
-        if (cityInfo->state != CITY_STATE_UNKNOWN) {
-            CitySizeDescription* citySizeDescription = &(wmSphereData[cityInfo->size]);
-            int cityX = cityInfo->x - wmWorldOffsetX;
-            int cityY = cityInfo->y - wmWorldOffsetY;
-            if (cityX >= 0 && cityX <= 472 - citySizeDescription->frmImage.getWidth()
-                && cityY >= 0 && cityY <= 465 - citySizeDescription->frmImage.getHeight()) {
-                wmInterfaceDrawCircleOverlay(cityInfo, citySizeDescription, wmBkWinBuf, cityX, cityY);
+    constexpr int PADDING = 100;
+
+    int viewportWidth = 472;
+    int viewportHeight = 465;
+
+    int bufferWidth = viewportWidth + PADDING * 2;
+    int bufferHeight = viewportHeight + PADDING * 2;
+
+    unsigned char* paddedBuf = (unsigned char*)malloc(bufferWidth * bufferHeight);
+    if (paddedBuf != nullptr) {
+        // Copy current wmBkWinBuf into center of paddedBuf
+        memset(paddedBuf, 0, bufferWidth * bufferHeight); // Clear padding
+
+        for (int y = 0; y < viewportHeight; y++) {
+            memcpy(
+                paddedBuf + bufferWidth * (y + PADDING) + PADDING,
+                wmBkWinBuf + y * WM_WINDOW_WIDTH,
+                viewportWidth);
+        }
+
+        // Draw cities onto a padded buffer
+        for (int index = 0; index < wmMaxAreaNum; index++) {
+            CityInfo* cityInfo = &wmAreaInfoList[index];
+            if (cityInfo->state != CITY_STATE_UNKNOWN) {
+                CitySizeDescription* citySizeDescription = &wmSphereData[cityInfo->size];
+                int cityX = cityInfo->x - wmWorldOffsetX + PADDING;
+                int cityY = cityInfo->y - wmWorldOffsetY + PADDING;
+
+                if (cityX >= 0 && cityX <= bufferWidth - citySizeDescription->frmImage.getWidth() &&
+                        cityY >= 0 && cityY <= bufferHeight - citySizeDescription->frmImage.getHeight()) {
+                        wmInterfaceDrawCircleOverlay(cityInfo, citySizeDescription, paddedBuf, cityX, cityY, bufferWidth);
+                }
             }
         }
+
+        // Copy center portion back to wmBkWinBuf
+        for (int y = 0; y < viewportHeight; y++) {
+            memcpy(
+                wmBkWinBuf + y * WM_WINDOW_WIDTH,
+                paddedBuf + bufferWidth * (y + PADDING) + PADDING,
+                viewportWidth);
+        }
+
+        free(paddedBuf);
     }
 
     // Hide unknown subtiles, dim unvisited.
@@ -5384,39 +5417,46 @@ static int wmMatchWorldPosToArea(int x, int y, int* areaIdxPtr)
     return 0;
 }
 
+// Function augmented to add destPitch to align city icons properly
 // 0x4C3FA8
-static int wmInterfaceDrawCircleOverlay(CityInfo* city, CitySizeDescription* citySizeDescription, unsigned char* dest, int x, int y)
+static int wmInterfaceDrawCircleOverlay(
+    CityInfo* city,
+    CitySizeDescription* citySizeDescription,
+    unsigned char* dest,
+    int x,
+    int y,
+    int destPitch)
 {
-    _dark_translucent_trans_buf_to_buf(citySizeDescription->frmImage.getData(),
+    _dark_translucent_trans_buf_to_buf(
+        citySizeDescription->frmImage.getData(),
         citySizeDescription->frmImage.getWidth(),
         citySizeDescription->frmImage.getHeight(),
         citySizeDescription->frmImage.getWidth(),
         dest,
         x,
         y,
-        WM_WINDOW_WIDTH,
+        destPitch,
         0x10000,
         circleBlendTable,
         _commonGrayTable);
 
-    // CE: Slightly increase whitespace between cirle and city name.
     int nameY = y + citySizeDescription->frmImage.getHeight() + 3;
-    int maxY = 464 - fontGetLineHeight();
+    int maxY = (464) + 200 - fontGetLineHeight(); // 200 for the PADDING
     if (nameY < maxY) {
         MessageListItem messageListItem;
         char name[40];
         if (wmAreaIsKnown(city->areaId)) {
-            // NOTE: Uninline.
             wmGetAreaName(city, name);
         } else {
             strncpy(name, getmsg(&wmMsgFile, &messageListItem, 1004), 40);
         }
 
         int width = fontGetStringWidth(name);
-        fontDrawText(dest + WM_WINDOW_WIDTH * nameY + x + citySizeDescription->frmImage.getWidth() / 2 - width / 2,
+        fontDrawText(
+            dest + destPitch * nameY + x + citySizeDescription->frmImage.getWidth() / 2 - width / 2,
             name,
             width,
-            WM_WINDOW_WIDTH,
+            destPitch,
             _colorTable[992] | FONT_SHADOW);
     }