Changeset 7e38970d in mainline for uspace/lib/gfx/src/coord.c

Timestamp:

2020-12-07T00:08:37Z (4 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

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

Children:

25f26600

Parents:

7a873f0 (diff), 8596474 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge branch 'jxsvoboda-gfx' into master

File:

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

uspace/lib/gfx/src/coord.c

@@ -39 +39 @@
 #include <stddef.h>
 
+/** Divide @a a by @a b and round towards negative numbers.
+ *
+ * Regular integer division always rounds towards zero. This is not useful
+ * e.g. for scaling down, where we always need to round towards negative
+ * numbers.
+ *
+ * @param a Dividend
+ * @param b Divisor
+ * @return Quotient
+ */
+gfx_coord_t gfx_coord_div_rneg(gfx_coord_t a, gfx_coord_t b)
+{
+        if ((a > 0 && b > 0) || (a < 0 && b < 0)) {
+                /* Result is non-negative, round towards zero */
+                return a / b;
+        } else {
+                /* Result is negative, round away from zero */
+                return (a - b + 1) / b;
+        }
+}
+
 /** Add two vectors.
  *
@@ -217 +238 @@
 }
 
+/** Center rectangle on rectangle.
+ *
+ * Translate rectangle @a a so that its center coincides with the
+ * center of rectangle @a b, saving the result in @a dest.
+ *
+ * @param a Rectnagle to translate
+ * @param b Rectangle on which to center
+ * @param dest Place to store resulting rectangle
+ */
+void gfx_rect_ctr_on_rect(gfx_rect_t *a, gfx_rect_t *b, gfx_rect_t *dest)
+{
+        gfx_coord2_t adim;
+        gfx_coord2_t bdim;
+
+        gfx_rect_dims(a, &adim);
+        gfx_rect_dims(b, &bdim);
+
+        dest->p0.x = b->p0.x + bdim.x / 2 - adim.x / 2;
+        dest->p0.y = b->p0.y + bdim.y / 2 - adim.y / 2;
+
+        dest->p1.x = dest->p0.x + adim.x;
+        dest->p1.y = dest->p0.y + adim.y;
+}
+
 /** Sort points of a rectangle.
  *