Recreate QPixmap in get_pixmap() if size differs

The pixmap should have the size requested and not the original size.
Note that it may be better to do resizing on the callee/method user side
as recreating a pixmap instead of scaling an existing one is expensive.

2 files changed, 16 insertions, 1 deletions

diff --git a/src/activitypub/apattachment.cpp b/src/activitypub/apattachment.cpp
index b5c82ce..db305ba 100644
--- a/src/activitypub/apattachment.cpp
+++ b/src/activitypub/apattachment.cpp
@@ -30,7 +30,14 @@ QString APAttachment::get_html_render(HtmlRenderDetails info) {
 }
 
 const QPixmap& APAttachment::get_pixmap(int width, int height) {
-    if (pixmap) return *pixmap;
+    // Recreating the pixmap if it doesn't have the requested dimensions is quite inefficent. So it's better for the callee to resize the image instead of relying on this function.
+    if (pixmap and pixmap_dimens.is_equal(width, height)) return *pixmap;
+    else if (pixmap)
+        delete pixmap;
+
+    // pixmap_dimens are correctly based on the requested/function argument width and height, and not the actual dimentions of the pixmap!
+    pixmap_dimens.height = height;
+    pixmap_dimens.width = width;
 
     if (width > 0 or height > 0) {
         QPixmap image(path_url);
diff --git a/src/activitypub/apattachment.h b/src/activitypub/apattachment.h
index f4e620b..83e9339 100644
--- a/src/activitypub/apattachment.h
+++ b/src/activitypub/apattachment.h
@@ -23,6 +23,14 @@ private:
     QString filename; // nicer descriptor of the attachment's path
 
     QPixmap* pixmap = nullptr;
+    struct {
+        int width = 0;
+        int height = 0;
+        // Compare with dimensions passed to get_pixmap()
+        inline bool is_equal(int comp_w, int comp_h) {
+            return width == comp_w and height == comp_h;
+        }
+    } pixmap_dimens; // requested dimensions of the pixmap
 };
 
 class APAttachmentList : public std::vector<APAttachment>, APBase {