Add ForceProportions image effect

ShareX.ImageEffectsLib/Forms/ImageEffectsForm.cs

@@ -129,6 +129,7 @@ private void AddAllEffectsToContextMenu()
                 typeof(Canvas),
                 typeof(Crop),
                 typeof(Flip),
+                typeof(ForceProportions),
                 typeof(Resize),
                 typeof(Rotate),
                 typeof(RoundedCorners),

ShareX.ImageEffectsLib/Manipulations/ForceProportions.cs

@@ -0,0 +1,131 @@
+#region License Information (GPL v3)
+
+/*
+    ShareX - A program that allows you to take screenshots and share any file type
+    Copyright (c) 2007-2020 ShareX Team
+
+    This program is free software; you can redistribute it and/or
+    modify it under the terms of the GNU General Public License
+    as published by the Free Software Foundation; either version 2
+    of the License, or (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+    Optionally you can also view the license at <http://www.gnu.org/licenses/>.
+*/
+
+#endregion License Information (GPL v3)
+
+using ShareX.HelpersLib;
+using System;
+using System.ComponentModel;
+using System.Drawing;
+using System.Windows.Forms;
+
+namespace ShareX.ImageEffectsLib
+{
+    internal class ForceProportions : ImageEffect
+    {
+        private int width = 1;
+        private int height = 1;
+
+        //[DefaultValue(typeof(Padding), "0, 0, 0, 0")]
+        public int Width
+        {
+            get {
+                return width;
+            }
+            set
+            {
+                width = Math.Max(1, value);
+            }
+        }
+        public int Height
+        {
+            get
+            {
+                return height;
+            }
+            set
+            {
+                height = Math.Max(1, value);
+            }
+        }
+
+        public enum ForceMethod
+        {
+            Grow,
+            Crop
+        }
+
+        public ForceMethod Method { get; set; } = ForceMethod.Grow;
+
+        public Color GrowFillColor { get; set; } = Color.FromArgb(0);
+
+        public ForceProportions()
+        {
+            this.ApplyDefaultPropertyValues();
+        }
+
+        public override Bitmap Apply(Bitmap bmp)
+        {
+            // NOTE: I don't know if input bitmap can have 0 as height
+            // TODO: remove this if it can't
+            if (bmp.Width < 1 || bmp.Height < 1)
+                return bmp;
+
+            float target_ratio = (float)width / (float)height;
+            float current_ratio = (float)bmp.Width / (float)bmp.Height;
+            int target_width = bmp.Width;
+            int target_height = bmp.Height;
+
+            bool is_target_wider = target_ratio > current_ratio;
+            if(Method == ForceMethod.Crop)
+            {
+                if (is_target_wider)
+                    target_height = (int)Math.Round(bmp.Width / target_ratio);
+                else
+                    target_width = (int)Math.Round(bmp.Height * target_ratio);
+                int margin_left = is_target_wider
+                    ? 0
+                    : (bmp.Width - target_width) / 2;
+                int margin_top = is_target_wider
+                    ? (bmp.Height - target_height) / 2
+                    : 0;
+                return ImageHelpers.CropBitmap(bmp, new Rectangle(margin_left, margin_top, target_width, target_height));
+            }
+            if(Method == ForceMethod.Grow)
+            {
+                if (is_target_wider)
+                    target_width = (int)Math.Round(bmp.Height * target_ratio);
+                else
+                    target_height = (int)Math.Round(bmp.Width / target_ratio);
+                int margin_hor = is_target_wider
+                    ? (target_width - bmp.Width) / 2
+                    : 0;
+                int margin_ver = is_target_wider
+                    ? 0
+                    : (target_height - bmp.Height) / 2;
+
+                Bitmap bmpResult = ImageHelpers.AddCanvas(bmp, new Padding(margin_hor, margin_ver, margin_hor, margin_ver), GrowFillColor);
+
+                if (bmpResult == null)
+                {
+                    return bmp;
+                }
+
+                bmp.Dispose();
+                return bmpResult;
+            }
+
+            return bmp;
+        }
+    }
+}

ShareX.ImageEffectsLib/ShareX.ImageEffectsLib.csproj

@@ -142,6 +142,7 @@
     </Compile>
     <Compile Include="ImageEffectPreset.cs" />
     <Compile Include="Manipulations\AutoCrop.cs" />
+    <Compile Include="Manipulations\ForceProportions.cs" />
     <Compile Include="Manipulations\Crop.cs" />
     <Compile Include="Manipulations\RoundedCorners.cs" />
     <Compile Include="Manipulations\Skew.cs" />