SharpDx：设置字符宽度

Question

我正在使用 SharpDX 编写 C# Direct2D 应用程序，但是我可以理解 answers/examples C++ 中提供的内容。

我想渲染文本并更改某些字符的宽度以使其看起来像图片：

字母B扩大到200%，字母D缩小到50%

在下面的代码中，我绘制了字形的几何图形所以可以改变几何体的宽度但这不是一个好的解决方案，因为几何绘图会像您在图片中看到的那样模糊。

总结起来有两个问题：

如何改变字符的宽度？

如何在不模糊的情况下绘制字母的几何形状。（可以用 ClearType 渲染几何图形吗？）

private void RenderGlyphRun1(FontFace1 fontFace)
{
    var Offsets = new List<GlyphOffset>();
    var fontEmSize_ = 12;
    GlyphRun glyphRun = new GlyphRun();
    glyphRun.FontFace = fontFace;
    glyphRun.FontSize = fontEmSize_;
    glyphRun.BidiLevel = 1;
    var left = 650f;
    var top = 50f;

    var baseLine = (float)(fontFace.Metrics.LineGap + fontFace.Metrics.Ascent) /
        fontFace.Metrics.DesignUnitsPerEm * glyphRun.FontSize;

    string textToDraw = "ABCDE";
    foreach (char letter in textToDraw)
    {
        Offsets.Add(new GlyphOffset());
    }

    var charArr = textToDraw.Select(x => (int)x).ToArray();
    glyphRun.Indices = fontFace.GetGlyphIndices(charArr);

    var metrics = fontFace.GetDesignGlyphMetrics(glyphRun.Indices, false);
    glyphRun.Advances = metrics.Select(x => (float)x.AdvanceWidth /
             fontFace.Metrics.DesignUnitsPerEm * glyphRun.FontSize).ToArray();

    glyphRun.Offsets = Offsets.ToArray();

    RenderTarget2D.BeginDraw();
    RenderTarget2D.Clear(SharpDX.Color.White);

    RenderTarget2D.DrawGlyphRun(new Vector2(left, top),
        glyphRun, new SharpDX.Direct2D1.SolidColorBrush(RenderTarget2D, SharpDX.Color.Black),
        MeasuringMode.Natural);

    top += baseLine;

    var pathGeometry = new PathGeometry(Factory2D);
    var geometrySink = pathGeometry.Open();

    fontFace.GetGlyphRunOutline(glyphRun.FontSize, glyphRun.Indices,
        glyphRun.Advances, glyphRun.Offsets, glyphRun.IsSideways,
        glyphRun.BidiLevel % 2 != 0, geometrySink);

    geometrySink.Close();
    geometrySink.Dispose();
    fontFace.Dispose();

    var matrix = new Matrix3x2()
    {
        M11 = 1,
        M12 = 0,
        M21 = 0,
        M22 = 1,
        M31 = left,
        M32 = top
    };

    var transformedGeometry = new TransformedGeometry(Factory2D, pathGeometry, matrix);
    var brushColor = (Color4)SharpDX.Color.Black;
    var brush = new SolidColorBrush(RenderTarget2D, brushColor);
    RenderTarget2D.FillGeometry(transformedGeometry, brush);

    pathGeometry.Dispose();
    transformedGeometry.Dispose();
    brush.Dispose();

    RenderTarget2D.EndDraw();
}

Answer 1

Direct2D 文本呈现功能分两部分提供：

1) DrawText 和 DrawTextLayout 方法，使调用者能够传递字符串和格式化参数，或传递多种格式的 DWrite 文本布局对象。这应该适合大多数来电者。

2) 第二种方式是渲染文本，公开为DrawGlyphRun方法，为已经知道他们想要渲染的字形位置的客户提供光栅化。以下两条通用规则有助于提高在 Direct2D 中绘图时的文本性能。

我现在看到您使用的是第二种方法，但是在第一种方法中，您可以将渲染设置为 ClearType :

RenderTarget2D.TextAntialiasMode = TextAntialiasMode.Cleartype;

我不确定如何将它包含在您的示例中，但 Sharp DX 示例如下所示：

using System;
using SharpDX;
using SharpDX.Direct2D1;
using SharpDX.DirectWrite;
using SharpDX.Samples;
using TextAntialiasMode = SharpDX.Direct2D1.TextAntialiasMode;

namespace TextRenderingApp
{
  public class Program : Direct2D1DemoApp
  {        
    public TextFormat TextFormat { get; private set; }
    public TextLayout TextLayout { get; private set; }

    protected override void Initialize(DemoConfiguration demoConfiguration)
    {
        base.Initialize(demoConfiguration);

        // Initialize a TextFormat
        TextFormat = new TextFormat(FactoryDWrite, "Calibri", 128) {TextAlignment = TextAlignment.Center, ParagraphAlignment = ParagraphAlignment.Center};

        RenderTarget2D.TextAntialiasMode = TextAntialiasMode.Cleartype;

        // Initialize a TextLayout
        TextLayout = new TextLayout(FactoryDWrite, "SharpDX D2D1 - DWrite", TextFormat, demoConfiguration.Width, demoConfiguration.Height);
    }


    protected override void Draw(DemoTime time)
    {
        base.Draw(time);

        // Draw the TextLayout
        RenderTarget2D.DrawTextLayout(new Vector2(0,0), TextLayout, SceneColorBrush, DrawTextOptions.None );
    }


    [STAThread]
    static void Main(string[] args)
    {
        Program program = new Program();
        program.Run(new DemoConfiguration("SharpDX DirectWrite Text Rendering Demo"));
    }
  }
}

样本取自：https://github.com/sharpdx/SharpDX-Samples/blob/master/Desktop/Direct2D1/TextRenderingApp

Answer 2

由于有些字母应该是窄的，有些是正常的，有些是宽的，你不能使用一个 GlyphRun，而必须创建 3 个不同的 GlyphRun.

要使任何 GlyphRun 的所有字母变宽或变窄：

将Transform配置为RenderTarget
绘制GlyphRun
Return原Transform

宽变换：RenderTarget2D.Transform = new SharpDX.Mathematics.Interop.RawMatrix3x2(1.5f, 0, 0, 1, 0, 0);

窄变换：RenderTarget2D.Transform = new SharpDX.Mathematics.Interop.RawMatrix3x2(0.5f, 0, 0, 1, 0, 0);

采用此解决方案后，您无需将 GlyphRun 转换为 geometry 并混淆模糊字母。

SharpDx：设置字符宽度

SharpDx: Setting character width

c#

c++

directx

sharpdx

directwrite