Changeset 1388f7f0 in mainline for uspace/lib/gfx/src/coord.c

Timestamp:

2020-02-21T10:50:48Z (5 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

265989d

Parents:

6c2aba3

git-author:

Jiri Svoboda <jiri@…> (2020-02-19 19:38:03)

git-committer:

Jiri Svoboda <jiri@…> (2020-02-21 10:50:48)

Message:

Support absolute movement events from input device

File:

• uspace/lib/gfx/src/coord.c (modified) (2 diffs)

uspace/lib/gfx/src/coord.c

@@ -62 +62 @@
 }
 
+/** Clip point coordinates to be within a rectangle.
+ *
+ * @param a Pixel coordinates
+ * @param clip Clipping rectangle
+ * @param d Place to store clipped coordinates
+ */
 void gfx_coord2_clip(gfx_coord2_t *a, gfx_rect_t *clip, gfx_coord2_t *d)
 {
@@ -74 +80 @@
         d->x = max(clip->p0.x, t.x);
         d->y = max(clip->p0.y, t.y);
+}
+
+/** Transform coordinates via rectangle to rectangle projection.
+ *
+ * Transform pixel coordinate via a projection that maps one rectangle
+ * onto another rectangle. The source rectangle must have both dimensions
+ * greater than one.
+ *
+ * @param a Pixel coordinates
+ * @param srect Source rectangle
+ * @param drect Destination rectangle
+ * @param d Place to store resulting coordinates.
+ */
+void gfx_coord2_project(gfx_coord2_t *a, gfx_rect_t *srect, gfx_rect_t *drect,
+    gfx_coord2_t *d)
+{
+        gfx_rect_t sr;
+        gfx_rect_t dr;
+
+        gfx_rect_points_sort(srect, &sr);
+        gfx_rect_points_sort(drect, &dr);
+
+        d->x = dr.p0.x + (a->x - sr.p0.x) * (dr.p1.x - dr.p0.x - 1) /
+            (sr.p1.x - sr.p0.x - 1);
+        d->y = dr.p0.y + (a->y - sr.p0.y) * (dr.p1.y - dr.p0.y - 1) /
+            (sr.p1.y - sr.p0.y - 1);
 }