diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/smallmap_gui.cpp | 45 |
1 files changed, 38 insertions, 7 deletions
diff --git a/src/smallmap_gui.cpp b/src/smallmap_gui.cpp index 0cdf9a4f3..51554367b 100644 --- a/src/smallmap_gui.cpp +++ b/src/smallmap_gui.cpp @@ -557,15 +557,16 @@ class SmallMapWindow : public Window { /** * Determine the tile relative to the base tile of the smallmap, and the pixel position at * that tile for a point in the smallmap. - * @param px Horizontal coordinate of the pixel. - * @param py Vertical coordinate of the pixel. + * @param px Horizontal coordinate of the pixel. + * @param py Vertical coordinate of the pixel. * @param sub[out] Pixel position at the tile (0..3). + * @param add_sub Add current #subscroll to the position. * @return Tile being displayed at the given position relative to #scroll_x and #scroll_y. * @note The #subscroll offset is already accounted for. */ - FORCEINLINE Point PixelToTile(int px, int py, int *sub) const + FORCEINLINE Point PixelToTile(int px, int py, int *sub, bool add_sub = true) const { - px += this->subscroll; // Total horizontal offset. + if (add_sub) px += this->subscroll; // Total horizontal offset. /* For each two rows down, add a x and a y tile, and * For each four pixels to the right, move a tile to the right. */ @@ -586,6 +587,37 @@ class SmallMapWindow : public Window { return pt; } + /** + * Compute base parameters of the smallmap such that tile (\a tx, \a ty) starts at pixel (\a x, \a y). + * @param tx Tile x coordinate. + * @param ty Tile y coordinate. + * @param x Non-negative horizontal position in the display where the tile starts. + * @param y Non-negative vertical position in the display where the tile starts. + * @param sub [out] Value of #subscroll needed. + * @return #scroll_x, #scroll_y values. + */ + Point ComputeScroll(int tx, int ty, int x, int y, int *sub) + { + assert(x >= 0 && y >= 0); + + int new_sub; + Point tile_xy = PixelToTile(x, y, &new_sub, false); + tx -= tile_xy.x; + ty -= tile_xy.y; + + Point scroll; + if (new_sub == 0) { + *sub = 0; + scroll.x = (tx + this->zoom) * TILE_SIZE; + scroll.y = (ty - this->zoom) * TILE_SIZE; + } else { + *sub = 4 - new_sub; + scroll.x = (tx + 2 * this->zoom) * TILE_SIZE; + scroll.y = (ty - 2 * this->zoom) * TILE_SIZE; + } + return scroll; + } + /** Initialize or change the zoom level. * @param change Way to change the zoom level. * @param zoom_pt Position to keep fixed while zooming. @@ -1287,9 +1319,8 @@ public: int sub; const NWidgetBase *wid = this->GetWidget<NWidgetBase>(SM_WIDGET_MAP); - Point tile = this->PixelToTile(wid->current_x / 2, wid->current_y / 2, &sub); - - this->SetNewScroll(pt.x - tile.x * TILE_SIZE, pt.y - tile.y * TILE_SIZE, sub); + Point sxy = this->ComputeScroll(pt.x / TILE_SIZE, pt.y / TILE_SIZE, max(0, (int)wid->current_x / 2 - 2), wid->current_y / 2, &sub); + this->SetNewScroll(sxy.x, sxy.y, sub); this->SetDirty(); } }; |