UGUI默认的文本没有显示下划线,颜色渐变等功能的,可以:
- 使用Image来模拟下划线,但对于多行文本的支持有问题.
- 使用TextMeshPro来做,但需要制作字体纹理集,如果要使用多种字体,则会更麻烦.
如果能让UGUI默认Text就支持,则是比较方便的.
代码如下:
using UnityEngine;
using UnityEngine.UI;
using System.Collections.Generic;
using XLua;
namespace DCG.UI
{
///对文本组建的扩展
/// stream = null;
// 可视的字符个数
private int characterCountVisible = 0;
override protected void Awake()
{
this.text = this.GetComponent();
if (this.text == null) return;
text.RegisterDirtyMaterialCallback(OnFontMaterialChanged);
}
#if UNITY_EDITOR
override protected void OnEnable()
{
this.text = this.GetComponent();
text.RegisterDirtyMaterialCallback(OnFontMaterialChanged);
}
#endif
private void OnFontMaterialChanged()
{
// font纹理发生变化时,在font中注册一个字符
text.font.RequestCharactersInTexture("*", text.fontSize, text.fontStyle);
}
protected override void OnDestroy()
{
text.UnregisterDirtyMaterialCallback(OnFontMaterialChanged);
base.OnDestroy();
}
/// 从font纹理中获取指定字符的uv
private Vector2 GetUnderlineCharUV()
{
CharacterInfo info;
if (text.font.GetCharacterInfo('*', out info, text.fontSize, text.fontStyle))
{
return (info.uvBottomLeft + info.uvBottomRight + info.uvTopLeft + info.uvTopRight) * 0.25f;
}
Debug.LogWarning("GetCharacterInfo failed");
return Vector2.zero;
}
override public void ModifyMesh(VertexHelper vh)
{
if (!IsActive() || (!this.useUnderline && !this.useAlign && !this.useGradientColor))
{
return;
}
// 当宽或高足够小则不处理
if (text.rectTransform.rect.size.x <= 0 || text.rectTransform.rect.size.y <= 0) return;
#if UNITY_EDITOR
_lineHeightHalf = this.lineHeight * .5f;
#endif
// cachedTextGenerator是当前实际显示出来的相关信息,cachedTextGeneratorForLayout是所有布局信息(包括看不到的)
this.characters = text.cachedTextGenerator.GetCharactersArray();
this.lines = text.cachedTextGenerator.GetLinesArray();
if (this.useUnderline && this.ignoreBreakSign)
{
this.textChars = this.text.text.ToCharArray();
}
// 使用characterCountVisible来得到真正显示的字符数量.characterCount会额外包含(在宽度不足)时候裁剪掉的(边缘)字符,会导致显示的下划线多一个空白的宽度
this.characterCountVisible = text.cachedTextGenerator.characterCountVisible;
/* stream是6个一组(对应三角形索引信息,左上角开始,顺时针)对应1个字(含空白)
0-1
\|
2
0
|\
3-2
数组索引:
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, ...]
对应三角形索引:
[0, 1, 2, 2, 3, 0, 4, 5, 6, 6, 7, 4,...]
*/
this.stream = new List();
vh.GetUIVertexStream(stream);
vh.Clear();
if (this.useAlign || this.useGradientColor)
{
var _offi = 0;
for (int i = 0; i < stream.Count; i += 6) // 单个字符
{
int charIdx = i / 6;
var offx = 0f;
var offy = 0f;
if (this.useAlign)
{
// 不能直接使用(wordSpace * charIdx)来计算每个字符在间距下的x偏移,
// 要判断该字符是否处于换行的第1个字符序列,如果是第1个应该重置为0,
// GetCharCursorPos()中在获取每个字符的起始位置时,也会将该偏移减掉.
var lineIndex = this.GetCharInLineIndex(charIdx);
if (this.lines[lineIndex].startCharIdx == charIdx)
{
_offi = 0;
}
offx = this.wordSpace * _offi;
offy = this.lineSpace * lineIndex;
_offi++;
}
for (int j = 0; j < 6; j++)
{
// 渐变色
if (this.useGradientColor)
{
this.SetGradientColors(i, j);
}
// 间距
if (this.useAlign)
{
this.DoAlign(i, j, offx, offy);
}
}
}
}
// 添加下划线
if (useUnderline)
{
if (!this.useCustomLineIndexArray)
{
this.DrawAllLinesLine(vh);
}
else
{
this.DrawCustomLine(vh);
}
}
vh.AddUIVertexTriangleStream(stream);
}
private void SetGradientColors(int i, int j)
{
if (gradientColors == null) gradientColors = new Color[6];
gradientColors[0] = gradientColor1;
gradientColors[1] = gradientColor2;
gradientColors[2] = gradientColor4;
gradientColors[3] = gradientColor4;
gradientColors[4] = gradientColor3;
gradientColors[5] = gradientColor1;
UIVertex uiv = stream[i + j];
uiv.color = gradientColors[j];
stream[i + j] = uiv;
}
private void DoAlign(int i, int j, float offx, float offy)
{
UIVertex uiv = stream[i + j];
var pos = uiv.position;
// pos.x += this.wordSpace * _offi;
// pos.y += this.lineSpace * lineIndex;
pos.x += offx;
pos.y += offy;
uiv.position = pos;
stream[i + j] = uiv;
}
/// 获取一个字符索引所在的行
private int GetCharInLineIndex(int charIndex)
{
var ei = this.lines.Length - 1;
for (int i = 0; i < ei; i++)
{
var line = lines[i];
if (charIndex >= line.startCharIdx && charIndex < lines[i + 1].startCharIdx) return i;
}
// 是否在最后一行
if (charIndex >= lines[ei].startCharIdx && charIndex < this.characters.Length) return ei;
return -1;
}
// 显示所有下划线
private void DrawAllLinesLine(VertexHelper vh)
{
var uv0 = this.GetUnderlineCharUV();
for (int i = 0; i < this.lines.Length; i++)
{
var line = this.lines[i];
var endIndex = 0;
if (i + 1 < this.lines.Length)
{
// 通过下一行的起始索引减1得到这一行最后一个字符索引位置
var nextLineStartCharIdx = this.lines[i + 1].startCharIdx;
// 与本行的相同,当文本宽度只够容纳一个字的时候,unity会产生一个空行,要排除改行
if (nextLineStartCharIdx == this.lines[i].startCharIdx) continue;
endIndex = nextLineStartCharIdx - 1;
}
else
{
// 最后一行的最后字符索引位置
if (this.characterCountVisible == 0) continue;
endIndex = this.characterCountVisible - 1;
}
var bottomY = this.GetLineBottomY(i);
var firstCharOff = line.startCharIdx * this.wordSpace;
this.AddUnderlineVertTriangle(vh, line.startCharIdx, endIndex, firstCharOff, bottomY, uv0);
}
}
// 显示自定义起止点下划线
private void DrawCustomLine(VertexHelper vh)
{
var uv0 = this.GetUnderlineCharUV();
var charsMaxIndex = this.characterCountVisible - 1;
var chars = text.text.ToCharArray();
for (int i = 0; i < this.customLineIndexArray.Length; i++)
{
var v2 = this.customLineIndexArray[i];
var startIndex = v2[0];
var endIndex = v2[1];
if (endIndex < startIndex)
{
startIndex = v2[1];
endIndex = v2[0];
}
if (startIndex < 0) startIndex = 0;
if (endIndex > charsMaxIndex) endIndex = charsMaxIndex;
if (startIndex >= this.characterCountVisible) continue;
var lineIndex0 = this.GetCharInLineIndex(startIndex);
var lineIndex1 = this.GetCharInLineIndex(endIndex);
if (lineIndex0 != lineIndex1)
{
// 跨行
for (int j = lineIndex0; j <= lineIndex1; j++)
{
var bottomY = this.GetLineBottomY(j);
var lineStartCharIndex = startIndex;
var lineEndCharIndex = endIndex;
if (j == lineIndex0)
{
// 第一行,从指定起始字索引到改行末尾字索引(改行末尾索引是下一行的起始索引-1得到)
lineEndCharIndex = lines[j + 1].startCharIdx - 1;
}
else if (j == lineIndex1)
{
// 最后一行,从改行起始字索引到指定字索引
lineStartCharIndex = lines[j].startCharIdx;
}
else
{
// 中间行,从改行起始字所以到该行末尾字索引
lineStartCharIndex = lines[j].startCharIdx;
lineEndCharIndex = lines[j + 1].startCharIdx - 1;
}
var firstCharOff = lines[j].startCharIdx * this.wordSpace;
this.AddUnderlineVertTriangle(vh, lineStartCharIndex, lineEndCharIndex, firstCharOff, bottomY, uv0);
}
}
else
{
// 在同一行
var bottomY = this.GetLineBottomY(lineIndex0);
var firstCharOff = lines[lineIndex0].startCharIdx * this.wordSpace;
this.AddUnderlineVertTriangle(vh, startIndex, endIndex, firstCharOff, bottomY, uv0);
}
}
}
private float GetLineBottomY(int lineIndex)
{
UILineInfo line = this.lines[lineIndex];
var bottomY = line.topY - (lineAlignToMiddle ? line.height * .5f : line.height) - lineOffset;
// bottomY是原始大小下的信息,但文本在不同分辨率下会被进一步缩放处理,所以要将比例带入计算
bottomY /= this.text.pixelsPerUnit;
if (this.useAlign)
{
bottomY += lineIndex * this.lineSpace;
}
return bottomY;
}
private Vector2 GetCharCursorPos(int charIdx, float firstCharOff)
{
var charInfo = this.characters[charIdx];
var cursorPos = charInfo.cursorPos;
// cursorPos是原始大小下的信息,但文本在不同分辨率下会被进一步缩放处理,所以要将比例带入计算
cursorPos /= this.text.pixelsPerUnit;
var rtf = (this.transform as RectTransform);
if (this.useAlign)
{
// 行的第1个字符在DoAlign()中是修正过偏移的,所有后面的所有字符都要相应使用此偏移
cursorPos.x += this.wordSpace * charIdx - firstCharOff;
}
return cursorPos;
}
private UIVertex[] underlineUIVertexs = new UIVertex[6];
private void AddUnderlineVertTriangle(VertexHelper vh, int startIndex, int endIndex, float firstCharOff, float bottomY, Vector2 uv0)
{
if (this.ignoreBreakSign && this.textChars[endIndex] == '\n')
{
// 跳过换行符
endIndex--;
}
if (endIndex < startIndex) return;
// 左上
var pos0 = new Vector3(this.GetCharCursorPos(startIndex, firstCharOff).x, bottomY + (this.lineHeightJustify ? this._lineHeightHalf : 0), 0);
// 左下, 向下扩展
var pos1 = new Vector3(pos0.x, pos0.y - this.lineHeight, 0);
// 右下. charWidth是原始大小下的信息,但文本在不同分辨率下会被进一步缩放处理,所以要将比例带入计算
var pos2 = new Vector3(this.GetCharCursorPos(endIndex, firstCharOff).x + characters[endIndex].charWidth / this.text.pixelsPerUnit, pos1.y, 0);
// 右上
var pos3 = new Vector3(pos2.x, pos0.y, 0);
// 按照stream存储的规范,构建6个顶点: 左上和右下是2个三角形的重叠,
UIVertex vert = UIVertex.simpleVert;
vert.color = this.lineColor;
vert.uv0 = uv0;
vert.position = pos0;
underlineUIVertexs[0] = vert;
underlineUIVertexs[3] = vert;
vert.position = pos1;
underlineUIVertexs[5] = vert;
vert.position = pos2;
underlineUIVertexs[2] = vert;
underlineUIVertexs[4] = vert;
vert.position = pos3;
underlineUIVertexs[1] = vert;
stream.AddRange(underlineUIVertexs);
}
}
}
部分效果图如下:
image.png
image.png
说明:
- 支持多行文本.
- 将下划线偏移到文字中部时可形成删除线.
- 支持对某个区间添加下划线(通过在customLineIndexArray中添加字的起止索引),需要将富文本标签和换行符也算到长度中.
- 在当前文字的顶点和三角形数组中添加额外的下划线顶点和三角形(AddUnderlineVertTriangle()方法),没有增加新的mesh和material等,没有过多额外性能开销.
- 但顶点需要一个uv信息,如果直接使用(0,0),(0,1)来做下划线uv的映射,会发现显示出来的是整张font纹理,只能通过font纹理中的某个有效区域(有字符的区域)的uv来给到顶点,这样顶点就能显示出来. 通过RequestCharactersInTexture()在font注册一个自定义字符,而且该字符是不会显示到文本的内容中的,该字符的uv就可以作为下划线顶点的映射(参考https://gist.github.com/QXSoftware/dee6b88041e8c10056e860b98388b2f9)
- char和line包含的信息是原始信息,需要将text的pixelsPerUnit(作为除数)带入到这些坐标和宽度的计算中,才能使得在不同分辨率下显示正确(代码第356行,370行,397行).
- 理论上可以自行解析富文本,对其增加自定义标签(比如"")来达到显示下划线或其它操作(比如间距)等的处理,需要在ModifyMesh()中对每个字的顶点信息做手动处理,进行手动排列等(此处没有进一步制作); 也可以对每个字的三角形做其它处理达到更多效果表现.
转载请注明出处: https://www.jianshu.com/p/1ec514e62606