From e7f66a88d67542d13764eb8b1441037c327beabe Mon Sep 17 00:00:00 2001
From: Bojidar Marinov <bojidar.marinov.bg@gmail.com>
Date: Tue, 19 Apr 2016 16:07:06 +0300
Subject: [PATCH] Add preview of the Camera2D's screen boundaries

Closes #3365
---
 scene/2d/camera_2d.cpp | 39 +++++++++++++++++++++++++++++++++------
 1 file changed, 33 insertions(+), 6 deletions(-)

diff --git a/scene/2d/camera_2d.cpp b/scene/2d/camera_2d.cpp
index 67c17337590..39d2367bc05 100644
--- a/scene/2d/camera_2d.cpp
+++ b/scene/2d/camera_2d.cpp
@@ -37,8 +37,7 @@ void Camera2D::_update_scroll() {
 		return;
 
 	if (get_tree()->is_editor_hint()) {
-	//	update(); //will just be drawn
-		//??
+		update(); //will just be drawn
 		return;
 	}
 
@@ -85,7 +84,7 @@ Matrix32 Camera2D::get_camera_transform()  {
 
 		if (anchor_mode==ANCHOR_MODE_DRAG_CENTER) {
 
-			if (h_drag_enabled) {
+			if (h_drag_enabled && !get_tree()->is_editor_hint()) {
 				camera_pos.x = MIN( camera_pos.x, (new_camera_pos.x + screen_size.x * 0.5 * drag_margin[MARGIN_RIGHT]));
 				camera_pos.x = MAX( camera_pos.x, (new_camera_pos.x - screen_size.x * 0.5 * drag_margin[MARGIN_LEFT]));
 			} else {
@@ -97,7 +96,7 @@ Matrix32 Camera2D::get_camera_transform()  {
 				}
 			}
 
-			if (v_drag_enabled) {
+			if (v_drag_enabled && !get_tree()->is_editor_hint()) {
 
 				camera_pos.y = MIN( camera_pos.y, (new_camera_pos.y + screen_size.y * 0.5 * drag_margin[MARGIN_BOTTOM]));
 				camera_pos.y = MAX( camera_pos.y, (new_camera_pos.y - screen_size.y * 0.5 * drag_margin[MARGIN_TOP]));
@@ -118,7 +117,7 @@ Matrix32 Camera2D::get_camera_transform()  {
 
 
 
-		if (smoothing_enabled) {
+		if (smoothing_enabled && !get_tree()->is_editor_hint()) {
 
 			float c = smoothing*get_fixed_process_delta_time();
 			smoothed_camera_pos = ((camera_pos-smoothed_camera_pos)*c)+smoothed_camera_pos;
@@ -258,6 +257,34 @@ void Camera2D::_notification(int p_what) {
 			viewport=NULL;
 
 		} break;
+		case NOTIFICATION_DRAW: {
+
+			if (!is_inside_tree() || !get_tree()->is_editor_hint())
+				break;
+
+			Color area_axis_color(0.5, 0.42, 0.87, 0.63);
+			float area_axis_width = 1;
+			if(current)
+				area_axis_width = 3;
+
+			Matrix32 inv_camera_transform = get_camera_transform().affine_inverse();
+			Size2 screen_size = get_viewport_rect().size;
+
+			Vector2 screen_endpoints[4]= {
+				inv_camera_transform.xform(Vector2(0, 0)),
+				inv_camera_transform.xform(Vector2(screen_size.width,0)),
+				inv_camera_transform.xform(Vector2(screen_size.width, screen_size.height)),
+				inv_camera_transform.xform(Vector2(0, screen_size.height))
+			};
+
+			Matrix32 inv_transform = get_transform().affine_inverse(); // undo global space
+			draw_set_transform(inv_transform.get_origin(), inv_transform.get_rotation(), inv_transform.get_scale());
+
+			for(int i=0;i<4;i++) {
+				draw_line(screen_endpoints[i], screen_endpoints[(i+1)%4], area_axis_color, area_axis_width);
+			}
+
+		} break;
 	}
 }
 
@@ -383,7 +410,7 @@ void Camera2D::force_update_scroll() {
 void Camera2D::set_follow_smoothing(float p_speed) {
 
 	smoothing=p_speed;
-	if (smoothing>0)
+	if (smoothing>0 && !(is_inside_tree() && get_tree()->is_editor_hint()))
 		set_fixed_process(true);
 	else
 		set_fixed_process(false);