1 files changed, 14 insertions, 5 deletions

diff --git a/ui.cpp b/ui.cpp
index 8cb9b59..327d577 100644
--- a/ui.cpp
+++ b/ui.cpp
@@ -147,6 +147,8 @@ void UI::Rect::clip(const Rect& other) {
 		w -= n;
 	if ((n = y + h - (other.y + other.h)) > 0)
 		h -= n;
+	if (w < 0) w = 0;
+	if (h < 0) h = 0;
 }
 
 void UI::Rect::shrink(int a) {
@@ -154,6 +156,8 @@ void UI::Rect::shrink(int a) {
 	y += a;
 	w -= a * 2;
 	h -= a * 2;
+	if (w < 0) w = 0;
+	if (h < 0) h = 0;
 }
 
 bool UI::Rect::contains(int px, int py) {
@@ -335,6 +339,8 @@ void UI::Vertex_Buffer::reset(const Rect& c) {
 
 void UI::Vertex_Buffer::set_clip(const Rect& r) {
 	clip = r;
+	assert(r.x >= 0 && r.y >= 0);
+	assert(r.w >= 0 && r.h >= 0);
 	if (next)
 		next->set_clip(r);
 }
@@ -442,10 +448,8 @@ void UI::destroy() {
 }
 
 void UI::layout(int w, int h) {
-	area_w = w;
-	area_h = h;
-	Rect avail(0, 0, w, h);
-	root->layout(avail);
+	area = Rect(0, 0, w, h);
+	root->layout(area);
 	layout_dirty = 0;
 }
 
@@ -475,7 +479,7 @@ void UI::update(Arena* s) {
 		}
 	}
 	if (layout_dirty)
-		layout(area_w, area_h);
+		layout(area.w, area.h);
 }
 
 void UI::render(Arena* s, Texture_Id target) {
@@ -757,6 +761,7 @@ UI::Rect UI::Container::layout(const Rect& avail) {
 	used.w = used.h = 0;
 	bound = avail;
 	clip = avail;
+	clip.clip(ui->area);
 	for (child = children; child; child = child->next) {
 		Rect r = child->layout(area);
 		area.y += r.h + padding;
@@ -788,6 +793,7 @@ UI::Rect UI::Toolbar::layout(const Rect& avail) {
 	bound = used;
 	bound.w = avail.w;
 	clip = bound;
+	clip.clip(ui->area);
 	return used;
 }
 
@@ -823,6 +829,7 @@ UI::Rect UI::Button::layout(const Rect& avail) {
 	bound = r;
 	clip = r;
 	clip.shrink(ui_padding);
+	clip.clip(ui->area);
 	return r;
 }
 
@@ -866,6 +873,7 @@ UI::Rect UI::Label::layout(const Rect& avail) {
 	bound = r;
 	clip = r;
 	clip.shrink(ui_padding);
+	clip.clip(ui->area);
 	return r;
 }
 
@@ -917,6 +925,7 @@ UI::Rect UI::Modal::layout(const Rect& avail) {
 	title_bar->layout(content_size);
 	bound = content_size;
 	clip = content_size;
+	clip.clip(ui->area);
 	return content_size;
 }