Unity 中忽略图片透明度的 Image 组件的修改版本

只需将此组件添加到画布中的空对象即可。请注意，仅支持简单 图像类型。

using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Sprites;
using UnityEngine.UI;
#if UNITY_2017_4 || UNITY_2018_2_OR_NEWER
using UnityEngine.U2D;
#endif#if UNITY_EDITOR
using UnityEditor;// Custom Editor to order the variables in the Inspector similar to Image component
[CustomEditor( typeof( PaddingIgnoringImage ) )]
[CanEditMultipleObjects]
public class PaddingIgnoringImageEditor : Editor
{private SerializedProperty colorProp, spriteProp, preserveAspectProp, useSpriteMeshProp;private GUIContent spriteLabel;private void OnEnable(){colorProp = serializedObject.FindProperty( "m_Color" );spriteProp = serializedObject.FindProperty( "m_Sprite" );useSpriteMeshProp = serializedObject.FindProperty( "m_UseSpriteMesh" );preserveAspectProp = serializedObject.FindProperty( "m_PreserveAspect" );spriteLabel = new GUIContent( "Source Image" );}public override void OnInspectorGUI(){serializedObject.Update();EditorGUILayout.PropertyField( colorProp );EditorGUILayout.PropertyField( spriteProp, spriteLabel );bool spriteAssigned = spriteProp.objectReferenceValue || spriteProp.hasMultipleDifferentValues;if( spriteAssigned ){EditorGUI.indentLevel++;EditorGUILayout.PropertyField( useSpriteMeshProp );EditorGUILayout.PropertyField( preserveAspectProp );EditorGUI.indentLevel--;}DrawPropertiesExcluding( serializedObject, "m_Script", "m_Color", "m_Sprite", "m_PreserveAspect", "m_UseSpriteMesh", "m_OnCullStateChanged" );serializedObject.ApplyModifiedProperties();if( spriteAssigned && GUILayout.Button( "Set Native Size", EditorStyles.miniButton ) ){foreach( Object target in targets ){PaddingIgnoringImage _target = target as PaddingIgnoringImage;if( _target ){Undo.RecordObject( _target.rectTransform, "Set Native Size" );_target.SetNativeSize();EditorUtility.SetDirty( _target );}}}}
}
#endif// Most of this code is a copy&paste of Unity's UnityEngine.UI.Image.cs
[RequireComponent( typeof( CanvasRenderer ) )]
public class PaddingIgnoringImage : MaskableGraphic, ILayoutElement
{[SerializeField]private Sprite m_Sprite;public Sprite sprite{get { return m_Sprite; }set{if( m_Sprite ){if( m_Sprite != value ){m_Sprite = value;SetAllDirty();TrackImage();}}else if( value ){m_Sprite = value;SetAllDirty();TrackImage();}}}[SerializeField]private bool m_PreserveAspect;public bool preserveAspect{get { return m_PreserveAspect; }set { if( m_PreserveAspect != value ) { m_PreserveAspect = value; SetVerticesDirty(); } }}[SerializeField]private bool m_UseSpriteMesh;public bool useSpriteMesh{get { return m_UseSpriteMesh; }set { if( m_UseSpriteMesh != value ) { m_UseSpriteMesh = value; SetVerticesDirty(); } }}public override Texture mainTexture { get { return sprite ? sprite.texture : s_WhiteTexture; } }public float pixelsPerUnit{get{float spritePixelsPerUnit = 100;if( sprite )spritePixelsPerUnit = sprite.pixelsPerUnit;float referencePixelsPerUnit = 100;if( canvas )referencePixelsPerUnit = canvas.referencePixelsPerUnit;return spritePixelsPerUnit / referencePixelsPerUnit;}}public override Material material{get{if( m_Material != null )return m_Material;if( sprite && sprite.associatedAlphaSplitTexture != null ){
#if UNITY_EDITORif( Application.isPlaying )
#endifreturn Image.defaultETC1GraphicMaterial;}return defaultMaterial;}set { base.material = value; }}protected override void OnEnable(){base.OnEnable();TrackImage();}protected override void OnDisable(){base.OnDisable();if( m_Tracked )UnTrackImage();}private Vector4 GetDrawingDimensions(){Vector4 padding = sprite ? DataUtility.GetPadding( sprite ) : Vector4.zero;Vector2 size = sprite ? sprite.rect.size : Vector2.zero;size -= new Vector2( padding.x + padding.z, padding.y + padding.w );Rect r = GetPixelAdjustedRect();if( preserveAspect && size.sqrMagnitude > 0f ){float spriteRatio = size.x / size.y;float rectRatio = r.width / r.height;if( spriteRatio > rectRatio ){float oldHeight = r.height;r.height = r.width * ( 1f / spriteRatio );r.y += ( oldHeight - r.height ) * rectTransform.pivot.y;}else{float oldWidth = r.width;r.width = r.height * spriteRatio;r.x += ( oldWidth - r.width ) * rectTransform.pivot.x;}}return new Vector4( r.x, r.y, r.x + r.width, r.y + r.height );}protected override void OnPopulateMesh( VertexHelper vh ){vh.Clear();Vector4 v = GetDrawingDimensions();Vector4 uv = sprite ? DataUtility.GetOuterUV( sprite ) : Vector4.zero;Color32 color32 = color;if( !sprite || !useSpriteMesh ){vh.AddVert( new Vector3( v.x, v.y ), color32, new Vector2( uv.x, uv.y ) );vh.AddVert( new Vector3( v.x, v.w ), color32, new Vector2( uv.x, uv.w ) );vh.AddVert( new Vector3( v.z, v.w ), color32, new Vector2( uv.z, uv.w ) );vh.AddVert( new Vector3( v.z, v.y ), color32, new Vector2( uv.z, uv.y ) );vh.AddTriangle( 0, 1, 2 );vh.AddTriangle( 2, 3, 0 );}else{Vector4 spritePadding = DataUtility.GetPadding( sprite );Vector2 spriteRectSize = sprite.rect.size;Vector2 spriteNonPaddingSize = spriteRectSize - new Vector2( spritePadding.x + spritePadding.z, spritePadding.y + spritePadding.w );Vector2 spritePivot = sprite.pivot;Vector2 spriteNormalizedPivot = new Vector2( ( spritePivot.x - spritePadding.x ) / spriteNonPaddingSize.x, ( spritePivot.y - spritePadding.y ) / spriteNonPaddingSize.y );Vector2 spriteBoundSize = Vector2.Scale( sprite.bounds.size, new Vector2( spriteNonPaddingSize.x / spriteRectSize.x, spriteNonPaddingSize.y / spriteRectSize.y ) );Vector2 drawingSize = new Vector2( v.z - v.x, v.w - v.y );Vector2 drawOffset = Vector2.Scale( rectTransform.pivot - spriteNormalizedPivot, drawingSize );Vector2[] vertices = sprite.vertices;Vector2[] uvs = sprite.uv;ushort[] triangles = sprite.triangles;for( int i = 0; i < vertices.Length; ++i )vh.AddVert( new Vector3( ( vertices[i].x / spriteBoundSize.x ) * drawingSize.x - drawOffset.x, ( vertices[i].y / spriteBoundSize.y ) * drawingSize.y - drawOffset.y ), color32, new Vector2( uvs[i].x, uvs[i].y ) );for( int i = 0; i < triangles.Length; i += 3 )vh.AddTriangle( triangles[i + 0], triangles[i + 1], triangles[i + 2] );}}public override void SetNativeSize(){if( sprite != null ){Vector4 padding = DataUtility.GetPadding( sprite );Vector2 size = sprite.rect.size;size -= new Vector2( padding.x + padding.z, padding.y + padding.w );float w = size.x / pixelsPerUnit;float h = size.y / pixelsPerUnit;rectTransform.anchorMax = rectTransform.anchorMin;rectTransform.sizeDelta = new Vector2( w, h );SetAllDirty();}}int ILayoutElement.layoutPriority { get { return 0; } }float ILayoutElement.minWidth { get { return 0f; } }float ILayoutElement.minHeight { get { return 0f; } }float ILayoutElement.flexibleWidth { get { return -1; } }float ILayoutElement.flexibleHeight { get { return -1; } }float ILayoutElement.preferredWidth { get { return sprite ? ( sprite.rect.size.x / pixelsPerUnit ) : 0f; } }float ILayoutElement.preferredHeight { get { return sprite ? ( sprite.rect.size.y / pixelsPerUnit ) : 0f; } }void ILayoutElement.CalculateLayoutInputHorizontal() { }void ILayoutElement.CalculateLayoutInputVertical() { }// Whether this is being tracked for Atlas Bindingprivate bool m_Tracked = false;#if UNITY_2017_4 || UNITY_2018_2_OR_NEWERprivate static List<PaddingIgnoringImage> m_TrackedTexturelessImages = new List<PaddingIgnoringImage>();private static bool s_Initialized;
#endifprivate void TrackImage(){if( sprite != null && sprite.texture == null ){
#if UNITY_2017_4 || UNITY_2018_2_OR_NEWERif( !s_Initialized ){SpriteAtlasManager.atlasRegistered += RebuildImage;s_Initialized = true;}m_TrackedTexturelessImages.Add( this );
#endifm_Tracked = true;}}private void UnTrackImage(){
#if UNITY_2017_4 || UNITY_2018_2_OR_NEWERm_TrackedTexturelessImages.Remove( this );
#endifm_Tracked = false;}#if UNITY_2017_4 || UNITY_2018_2_OR_NEWERprivate static void RebuildImage( SpriteAtlas spriteAtlas ){for( int i = m_TrackedTexturelessImages.Count - 1; i >= 0; i-- ){PaddingIgnoringImage image = m_TrackedTexturelessImages[i];if( spriteAtlas.CanBindTo( image.sprite ) ){image.SetAllDirty();m_TrackedTexturelessImages.RemoveAt( i );}}}
#endif
}