我正在为Windows编写化学分子编辑器。因为它必须在Word加载项中使用,所以我被限制使用WPF来渲染结构。除了一个微小的琐碎点之外,这种方法运作得很好。
我使用GlyphRuns渲染原子标签,它们总是略微向右移位。如果您查看屏幕截图,您会看到有一个领先的空白,特别是H2N和Hg原子标签。为什么?获得字形运行的轮廓几何体时,您将获得白色背景。
GlyphRun类的记录非常糟糕,我无法看到要修改哪些属性以精确定位我想要的文本。所以任何尝试的建议都会受到欢迎。
更新:我被要求提供样品。代码很复杂,但并非无偿,所以我将其缩减为专注于基本要素:
public void MeasureAtCenter(Point center)
{
GlyphInfo = GlyphUtils.GetGlyphsAndInfo(Text, PixelsPerDip, out GlyphRun groupGlyphRun, center, _glyphTypeface, TypeSize);
//compensate the main offset vector for any descenders
Vector mainOffset = GlyphUtils.GetOffsetVector(groupGlyphRun, AtomShape.SymbolSize) + new Vector(0.0, -MaxBaselineOffset) + new Vector(-FirstBearing(groupGlyphRun), 0.0);
TextRun = groupGlyphRun;
TextMetrics = new AtomTextMetrics
{
BoundingBox = groupGlyphRun.GetBoundingBox(center + mainOffset),
Geocenter = center,
TotalBoundingBox = groupGlyphRun.GetBoundingBox(center + mainOffset),
OffsetVector = mainOffset
};
}
public static GlyphInfo GetGlyphs(string symbolText, GlyphTypeface glyphTypeFace, double size)
{
ushort[] glyphIndexes = new ushort[symbolText.Length];
double[] advanceWidths = new double[symbolText.Length];
double[] uprightBaselineOffsets = new double[symbolText.Length];
double totalWidth = 0;
for (int n = 0; n < symbolText.Length; n++)
{
ushort glyphIndex = glyphTypeFace.CharacterToGlyphMap[symbolText[n]];
glyphIndexes[n] = glyphIndex;
double width = glyphTypeFace.AdvanceWidths[glyphIndex] * size;
advanceWidths[n] = width;
double ubo = glyphTypeFace.DistancesFromHorizontalBaselineToBlackBoxBottom[glyphIndex] * size;
uprightBaselineOffsets[n] = ubo;
totalWidth += width;
}
return new GlyphInfo { AdvanceWidths = advanceWidths, Indexes = glyphIndexes, Width = totalWidth, UprightBaselineOffsets = uprightBaselineOffsets };
}
public static GlyphUtils.GlyphInfo GetGlyphsAndInfo(string symbolText, float pixelsPerDip, out GlyphRun hydrogenGlyphRun, Point point, GlyphTypeface glyphTypeFace, double symbolSize)
{
//measure the H atom first
var glyphInfo = GlyphUtils.GetGlyphs(symbolText, glyphTypeFace, symbolSize);
hydrogenGlyphRun = GlyphUtils.GetGlyphRun(glyphInfo, glyphTypeFace,
symbolSize, pixelsPerDip, point);
//work out exactly how much we should offset from the center to get to the bottom left
return glyphInfo;
}
public static Vector GetOffsetVector(GlyphRun glyphRun, double symbolSize)
{
Rect rect = glyphRun.ComputeInkBoundingBox();
//Vector offset = (rect.BottomLeft - rect.TopRight) / 2;
Vector offset = new Vector(-rect.Width / 2, glyphRun.GlyphTypeface.CapsHeight * symbolSize / 2);
return offset;
}