From 041431d966bc0afc2f6c2b5fdbdf83b6d18b1b66 Mon Sep 17 00:00:00 2001
From: Paul Chote <pchote@users.noreply.github.com>
Date: Tue, 5 Dec 2017 16:26:44 +0000
Subject: [PATCH] Add ISpriteSequence.Bounds and
 Animation(WithOffset).ScreenBounds.

The bounds define the smallest Rectangle that covers all frames within a sequence.
---
 OpenRA.Game/Graphics/Animation.cs             | 12 ++++++++
 OpenRA.Game/Graphics/AnimationWithOffset.cs   |  9 ++++++
 OpenRA.Game/Graphics/SequenceProvider.cs      |  3 +-
 .../Graphics/DefaultSpriteSequence.cs         | 30 +++++++++++++++++++
 4 files changed, 53 insertions(+), 1 deletion(-)

diff --git a/OpenRA.Game/Graphics/Animation.cs b/OpenRA.Game/Graphics/Animation.cs
index f93118e353..3e2880ef07 100644
--- a/OpenRA.Game/Graphics/Animation.cs
+++ b/OpenRA.Game/Graphics/Animation.cs
@@ -11,6 +11,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Drawing;
 using System.Linq;
 using OpenRA.Support;
 
@@ -66,6 +67,17 @@ namespace OpenRA.Graphics
 			return new IRenderable[] { imageRenderable };
 		}
 
+		public Rectangle ScreenBounds(WorldRenderer wr, WPos pos, WVec offset, float scale)
+		{
+			var xy = wr.ScreenPxPosition(pos) + wr.ScreenPxOffset(offset);
+			var cb = CurrentSequence.Bounds;
+			return Rectangle.FromLTRB(
+				xy.X + (int)(cb.Left * scale),
+				xy.Y + (int)(cb.Top * scale),
+				xy.X + (int)(cb.Right * scale),
+				xy.Y + (int)(cb.Bottom * scale));
+		}
+
 		public IEnumerable<IRenderable> Render(WPos pos, PaletteReference palette)
 		{
 			return Render(pos, WVec.Zero, 0, palette, 1f);
diff --git a/OpenRA.Game/Graphics/AnimationWithOffset.cs b/OpenRA.Game/Graphics/AnimationWithOffset.cs
index 47e44008cc..3c191b011a 100644
--- a/OpenRA.Game/Graphics/AnimationWithOffset.cs
+++ b/OpenRA.Game/Graphics/AnimationWithOffset.cs
@@ -11,6 +11,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Drawing;
 
 namespace OpenRA.Graphics
 {
@@ -44,6 +45,14 @@ namespace OpenRA.Graphics
 			return Animation.Render(center, offset, z, pal, scale);
 		}
 
+		public Rectangle ScreenBounds(Actor self, WorldRenderer wr, float scale)
+		{
+			var center = self.CenterPosition;
+			var offset = OffsetFunc != null ? OffsetFunc() : WVec.Zero;
+
+			return Animation.ScreenBounds(wr, center, offset, scale);
+		}
+
 		public static implicit operator AnimationWithOffset(Animation a)
 		{
 			return new AnimationWithOffset(a, null, null, null);
diff --git a/OpenRA.Game/Graphics/SequenceProvider.cs b/OpenRA.Game/Graphics/SequenceProvider.cs
index 93678d96ec..5333ccd107 100644
--- a/OpenRA.Game/Graphics/SequenceProvider.cs
+++ b/OpenRA.Game/Graphics/SequenceProvider.cs
@@ -11,7 +11,7 @@
 
 using System;
 using System.Collections.Generic;
-using System.Linq;
+using System.Drawing;
 using OpenRA.FileSystem;
 
 namespace OpenRA.Graphics
@@ -31,6 +31,7 @@ namespace OpenRA.Graphics
 		int ShadowStart { get; }
 		int ShadowZOffset { get; }
 		int[] Frames { get; }
+		Rectangle Bounds { get; }
 
 		Sprite GetSprite(int frame);
 		Sprite GetSprite(int frame, int facing);
diff --git a/OpenRA.Mods.Common/Graphics/DefaultSpriteSequence.cs b/OpenRA.Mods.Common/Graphics/DefaultSpriteSequence.cs
index c1335ef449..8619732db7 100644
--- a/OpenRA.Mods.Common/Graphics/DefaultSpriteSequence.cs
+++ b/OpenRA.Mods.Common/Graphics/DefaultSpriteSequence.cs
@@ -90,6 +90,7 @@ namespace OpenRA.Mods.Common.Graphics
 		public int ShadowStart { get; private set; }
 		public int ShadowZOffset { get; private set; }
 		public int[] Frames { get; private set; }
+		public Rectangle Bounds { get; private set; }
 
 		protected virtual string GetSpriteSrc(ModData modData, TileSet tileSet, string sequence, string animation, string sprite, Dictionary<string, MiniYaml> d)
 		{
@@ -270,6 +271,17 @@ namespace OpenRA.Mods.Common.Graphics
 						"{5}: Sequence {0}.{1}'s shadow frames use frames [{2}..{3}], but only [0..{4}] actually exist"
 						.F(sequence, animation, ShadowStart, ShadowStart + Facings * Stride - 1, sprites.Length - 1,
 							info.Nodes[0].Location));
+
+				var boundSprites = SpriteBounds(sprites, Frames, Start, Facings, Length);
+				if (ShadowStart > 0)
+					boundSprites = boundSprites.Concat(SpriteBounds(sprites, Frames, ShadowStart, Facings, Length));
+
+				if (boundSprites.Any())
+				{
+					Bounds = boundSprites.First();
+					foreach (var b in boundSprites.Skip(1))
+						Bounds = Rectangle.Union(Bounds, b);
+				}
 			}
 			catch (FormatException f)
 			{
@@ -277,6 +289,24 @@ namespace OpenRA.Mods.Common.Graphics
 			}
 		}
 
+		/// <summary>Returns the bounds of all of the sprites that can appear in this animation</summary>
+		static IEnumerable<Rectangle> SpriteBounds(Sprite[] sprites, int[] frames, int start, int facings, int length)
+		{
+			for (var facing = 0; facing < facings; facing++)
+			{
+				for (var frame = 0; frame < length; frame++)
+				{
+					var i = frame * facings + facing;
+					var s = frames != null ? sprites[frames[i]] : sprites[start + i];
+					if (!s.Bounds.IsEmpty)
+						yield return new Rectangle(
+							(int)(s.Offset.X - s.Size.X / 2),
+							(int)(s.Offset.Y - s.Size.Y / 2),
+							s.Bounds.Width, s.Bounds.Height);
+				}
+			}
+		}
+
 		public Sprite GetSprite(int frame)
 		{
 			return GetSprite(Start, frame, 0);