clipping and viewport improvements.

1 files changed, 44 insertions, 0 deletions

diff --git a/rect.c b/rect.c
index c72c66e..e3d3948 100644
--- a/rect.c
+++ b/rect.c
@@ -19,6 +19,24 @@ Rect* rect_clip(Rect* r, const Rect* c) {
 	return r;
 }
 
+Rect* rect_clipr(Rect* r, const int* c) {
+	int n;
+	int x = r->x, y = r->y;
+	if ((n = c[0] - r->x) > 0) {
+		r->w -= n;
+		r->x += n;
+	}
+	if ((n = c[1] - r->y) > 0) {
+		r->h -= n;
+		r->y += n;
+	}
+	if ((n = x + r->w - c[2]) > 0)
+		r->w -= n;
+	if ((n = y + r->h - c[3]) > 0)
+		r->h -= n;
+	return r;
+}
+
 Rect* rect_clips(Rect* r, Rect* s, const Rect* c) {
 	int n;
 	int x = r->x, y = r->y;
@@ -44,3 +62,29 @@ Rect* rect_clips(Rect* r, Rect* s, const Rect* c) {
 	}
 	return r;
 }
+
+Rect* rect_clipsr(Rect* r, Rect* s, const int* c) {
+	int n;
+	int x = r->x, y = r->y;
+	if ((n = c[0] - r->x) > 0) {
+		r->w -= n;
+		r->x += n;
+		s->w -= n;
+		s->x += n;
+	}
+	if ((n = c[1] - r->y) > 0) {
+		r->h -= n;
+		r->y += n;
+		s->h -= n;
+		s->y += n;
+	}
+	if ((n = x + r->w - c[2]) > 0) {
+		r->w -= n;
+		s->w -= n;
+	}
+	if ((n = y + r->h - c[3]) > 0) {
+		r->h -= n;
+		s->h -= n;
+	}
+	return r;
+}