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MLEM/MLEM/Font/GenericFont.cs
2024-04-10 20:45:16 +02:00

466 lines
27 KiB
C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using MLEM.Formatting;
using MLEM.Formatting.Codes;
using MLEM.Misc;
namespace MLEM.Font {
/// <summary>
/// Represents a font with additional abilities.
/// <seealso cref="GenericSpriteFont"/>
/// </summary>
public abstract class GenericFont : GenericDataHolder {
/// <summary>
/// This field holds the unicode representation of a one em space.
/// This is a character that isn't drawn, but has the same width as <see cref="LineHeight"/>.
/// Whereas a regular <see cref="SpriteFont"/> would have to explicitly support this character for width calculations, generic fonts implicitly support it in <see cref="MeasureString(string,bool)"/>.
/// </summary>
public const char Emsp = '\u2003';
/// <inheritdoc cref="Emsp"/>
[Obsolete("Use the Emsp field instead.")]
public const char OneEmSpace = GenericFont.Emsp;
/// <summary>
/// This field holds the unicode representation of a non-breaking space.
/// Whereas a regular <see cref="SpriteFont"/> would have to explicitly support this character for width calculations, generic fonts implicitly support it in <see cref="MeasureString(string,bool)"/>.
/// </summary>
public const char Nbsp = '\u00A0';
/// <summary>
/// This field holds the unicode representation of a zero-width space.
/// Whereas a regular <see cref="SpriteFont"/> would have to explicitly support this character for width calculations and string splitting, generic fonts implicitly support it in <see cref="MeasureString(string,bool)"/> and <see cref="SplitString(string,float,float)"/>.
/// </summary>
public const char Zwsp = '\u200B';
/// <summary>
/// The bold version of this font.
/// </summary>
public abstract GenericFont Bold { get; }
/// <summary>
/// The italic version of this font.
/// </summary>
public abstract GenericFont Italic { get; }
/// <summary>
/// The height of each line of text of this font.
/// This is the value that the text's draw position is offset by every time a newline character is reached.
/// </summary>
public abstract float LineHeight { get; }
/// <summary>
/// Measures the width of the given code point with the default scale for use in <see cref="MeasureString(string,bool)"/>.
/// Note that this method does not support <see cref="Nbsp"/>, <see cref="Zwsp"/> and <see cref="Emsp"/> for most generic fonts, which is why <see cref="MeasureString(string,bool)"/> should be used even for single characters.
/// </summary>
/// <param name="codePoint">The code point whose width to calculate</param>
/// <returns>The width of the given character with the default scale</returns>
protected abstract float MeasureCharacter(int codePoint);
/// <summary>
/// Draws the given code point with the given data for use in <see cref="DrawString(Microsoft.Xna.Framework.Graphics.SpriteBatch,System.Text.StringBuilder,Microsoft.Xna.Framework.Vector2,Microsoft.Xna.Framework.Color,float,Microsoft.Xna.Framework.Vector2,Microsoft.Xna.Framework.Vector2,Microsoft.Xna.Framework.Graphics.SpriteEffects,float)"/>.
/// Note that this method should only be called internally for rendering of more complex strings, like in <see cref="TextFormatter"/> <see cref="Code"/> implementations.
/// </summary>
/// <param name="batch">The sprite batch to draw with.</param>
/// <param name="codePoint">The code point which will be drawn.</param>
/// <param name="character">A string representation of the character which will be drawn.</param>
/// <param name="position">The drawing location on screen.</param>
/// <param name="color">A color mask.</param>
/// <param name="rotation">A rotation of this character.</param>
/// <param name="scale">A scaling of this character.</param>
/// <param name="effects">Modificators for drawing. Can be combined.</param>
/// <param name="layerDepth">A depth of the layer of this character.</param>
public abstract void DrawCharacter(SpriteBatch batch, int codePoint, string character, Vector2 position, Color color, float rotation, Vector2 scale, SpriteEffects effects, float layerDepth);
///<inheritdoc cref="SpriteBatch.DrawString(SpriteFont,string,Vector2,Color,float,Vector2,float,SpriteEffects,float)"/>
public void DrawString(SpriteBatch batch, string text, Vector2 position, Color color, float rotation, Vector2 origin, Vector2 scale, SpriteEffects effects, float layerDepth) {
this.DrawString(batch, new CodePointSource(text), position, color, rotation, origin, scale, effects, layerDepth);
}
///<inheritdoc cref="SpriteBatch.DrawString(SpriteFont,string,Vector2,Color,float,Vector2,float,SpriteEffects,float)"/>
public void DrawString(SpriteBatch batch, StringBuilder text, Vector2 position, Color color, float rotation, Vector2 origin, Vector2 scale, SpriteEffects effects, float layerDepth) {
this.DrawString(batch, new CodePointSource(text), position, color, rotation, origin, scale, effects, layerDepth);
}
///<inheritdoc cref="SpriteBatch.DrawString(SpriteFont,string,Vector2,Color,float,Vector2,float,SpriteEffects,float)"/>
public void DrawString(SpriteBatch batch, string text, Vector2 position, Color color, float rotation, Vector2 origin, float scale, SpriteEffects effects, float layerDepth) {
this.DrawString(batch, text, position, color, rotation, origin, new Vector2(scale), effects, layerDepth);
}
///<inheritdoc cref="SpriteBatch.DrawString(SpriteFont,string,Vector2,Color,float,Vector2,float,SpriteEffects,float)"/>
public void DrawString(SpriteBatch batch, StringBuilder text, Vector2 position, Color color, float rotation, Vector2 origin, float scale, SpriteEffects effects, float layerDepth) {
this.DrawString(batch, text, position, color, rotation, origin, new Vector2(scale), effects, layerDepth);
}
///<inheritdoc cref="SpriteBatch.DrawString(SpriteFont,string,Vector2,Color,float,Vector2,float,SpriteEffects,float)"/>
public void DrawString(SpriteBatch batch, string text, Vector2 position, Color color) {
this.DrawString(batch, text, position, color, 0, Vector2.Zero, Vector2.One, SpriteEffects.None, 0);
}
///<inheritdoc cref="SpriteBatch.DrawString(SpriteFont,string,Vector2,Color,float,Vector2,float,SpriteEffects,float)"/>
public void DrawString(SpriteBatch batch, StringBuilder text, Vector2 position, Color color) {
this.DrawString(batch, text, position, color, 0, Vector2.Zero, Vector2.One, SpriteEffects.None, 0);
}
/// <summary>
/// Measures the width of the given string when drawn with this font's underlying font.
/// This method uses <see cref="MeasureCharacter"/> internally to calculate the size of known characters and calculates additional characters like <see cref="Nbsp"/>, <see cref="Zwsp"/> and <see cref="Emsp"/>.
/// If the text contains newline characters (\n), the size returned will represent a rectangle that encompasses the width of the longest line and the string's full height.
/// </summary>
/// <param name="text">The text whose size to calculate</param>
/// <param name="ignoreTrailingSpaces">Whether trailing whitespace should be ignored in the returned size, causing the end of each line to be effectively trimmed</param>
/// <returns>The size of the string when drawn with this font</returns>
public Vector2 MeasureString(string text, bool ignoreTrailingSpaces = false) {
return this.MeasureString(new CodePointSource(text), ignoreTrailingSpaces);
}
/// <inheritdoc cref="MeasureString(string,bool)"/>
public Vector2 MeasureString(StringBuilder text, bool ignoreTrailingSpaces = false) {
return this.MeasureString(new CodePointSource(text), ignoreTrailingSpaces);
}
/// <summary>
/// Truncates a string to a given width. If the string's displayed area is larger than the maximum width, the string is cut off.
/// Optionally, the string can be cut off a bit sooner, adding the <paramref name="ellipsis"/> at the end instead.
/// </summary>
/// <param name="text">The text to truncate</param>
/// <param name="width">The maximum width, in display pixels based on the font and scale</param>
/// <param name="scale">The scale to use for width measurements</param>
/// <param name="fromBack">If the string should be truncated from the back rather than the front</param>
/// <param name="ellipsis">The characters to add to the end of the string if it is too long</param>
/// <returns>The truncated string, or the same string if it is shorter than the maximum width</returns>
public string TruncateString(string text, float width, float scale, bool fromBack = false, string ellipsis = "") {
return GenericFont.TruncateString(Enumerable.Repeat(new DecoratedCodePointSource(new CodePointSource(text), this, 0), 1), width, scale, fromBack, ellipsis).First().ToString();
}
/// <inheritdoc cref="TruncateString(string,float,float,bool,string)"/>
public StringBuilder TruncateString(StringBuilder text, float width, float scale, bool fromBack = false, string ellipsis = "") {
return GenericFont.TruncateString(Enumerable.Repeat(new DecoratedCodePointSource(new CodePointSource(text), this, 0), 1), width, scale, fromBack, ellipsis).First();
}
/// <summary>
/// Splits a string to a given maximum width, adding newline characters between each line.
/// Also splits long words and supports zero-width spaces and takes into account existing newline characters in the passed <paramref name="text"/>.
/// See <see cref="SplitStringSeparate(string,float,float)"/> for a method that differentiates between existing newline characters and splits due to maximum width.
/// </summary>
/// <param name="text">The text to split into multiple lines</param>
/// <param name="width">The maximum width that each line should have</param>
/// <param name="scale">The scale to use for width measurements</param>
/// <returns>The split string, containing newline characters at each new line</returns>
public string SplitString(string text, float width, float scale) {
return string.Join("\n", this.SplitStringSeparate(text, width, scale));
}
/// <inheritdoc cref="SplitString(string,float,float)"/>
public string SplitString(StringBuilder text, float width, float scale) {
return string.Join("\n", this.SplitStringSeparate(text, width, scale));
}
/// <summary>
/// Splits a string to a given maximum width and returns each split section as a separate string.
/// Note that existing new lines are taken into account for line length, but not split in the resulting strings.
/// This method differs from <see cref="SplitString(string,float,float)"/> in that it differentiates between pre-existing newline characters and splits due to maximum width.
/// </summary>
/// <param name="text">The text to split into multiple lines</param>
/// <param name="width">The maximum width that each line should have</param>
/// <param name="scale">The scale to use for width measurements</param>
/// <returns>The split string as an enumerable of split sections</returns>
public IEnumerable<string> SplitStringSeparate(string text, float width, float scale) {
return GenericFont.SplitStringSeparate(Enumerable.Repeat(new DecoratedCodePointSource(new CodePointSource(text), this, 0), 1), width, scale).First();
}
/// <inheritdoc cref="SplitStringSeparate(string,float,float)"/>
public IEnumerable<string> SplitStringSeparate(StringBuilder text, float width, float scale) {
return GenericFont.SplitStringSeparate(Enumerable.Repeat(new DecoratedCodePointSource(new CodePointSource(text), this, 0), 1), width, scale).First();
}
/// <summary>
/// Calculates a transformation matrix for drawing a string with the given data.
/// </summary>
/// <param name="position">The position to draw at.</param>
/// <param name="rotation">The rotation to draw with.</param>
/// <param name="origin">The origin to subtract from the position.</param>
/// <param name="scale">The scale to draw with.</param>
/// <param name="effects">The flipping to draw with.</param>
/// <param name="flipSize">The size of the string, which is only used when <paramref name="effects"/> is not <see cref="SpriteEffects.None"/>.</param>
/// <returns>A transformation matrix.</returns>
public Matrix CalculateStringTransform(Vector2 position, float rotation, Vector2 origin, Vector2 scale, SpriteEffects effects, Vector2 flipSize) {
var (flipX, flipY) = (0F, 0F);
var flippedV = (effects & SpriteEffects.FlipVertically) != 0;
var flippedH = (effects & SpriteEffects.FlipHorizontally) != 0;
if (flippedV || flippedH) {
if (flippedH) {
origin.X *= -1;
flipX = -flipSize.X;
}
if (flippedV) {
origin.Y *= -1;
flipY = this.LineHeight - flipSize.Y;
}
}
var trans = Matrix.Identity;
if (rotation == 0) {
trans.M11 = flippedH ? -scale.X : scale.X;
trans.M22 = flippedV ? -scale.Y : scale.Y;
trans.M41 = (flipX - origin.X) * trans.M11 + position.X;
trans.M42 = (flipY - origin.Y) * trans.M22 + position.Y;
} else {
var sin = (float) Math.Sin(rotation);
var cos = (float) Math.Cos(rotation);
trans.M11 = (flippedH ? -scale.X : scale.X) * cos;
trans.M12 = (flippedH ? -scale.X : scale.X) * sin;
trans.M21 = (flippedV ? -scale.Y : scale.Y) * -sin;
trans.M22 = (flippedV ? -scale.Y : scale.Y) * cos;
trans.M41 = (flipX - origin.X) * trans.M11 + (flipY - origin.Y) * trans.M21 + position.X;
trans.M42 = (flipX - origin.X) * trans.M12 + (flipY - origin.Y) * trans.M22 + position.Y;
}
return trans;
}
/// <summary>
/// Moves the passed <paramref name="charPos"/> based on the given flipping data.
/// </summary>
/// <param name="charPos">The position to move.</param>
/// <param name="effects">The flipping to move based on.</param>
/// <param name="charSize">The size of the object to move, which is only used when <paramref name="effects"/> is not <see cref="SpriteEffects.None"/>.</param>
/// <returns>The moved position.</returns>
public Vector2 MoveFlipped(Vector2 charPos, SpriteEffects effects, Vector2 charSize) {
if ((effects & SpriteEffects.FlipHorizontally) != 0)
charPos.X += charSize.X;
if ((effects & SpriteEffects.FlipVertically) != 0)
charPos.Y += charSize.Y - this.LineHeight;
return charPos;
}
/// <summary>
/// Transforms the position of a single character to draw.
/// In general, it is efficient to calculate the transformation matrix once at the start (using <see cref="CalculateStringTransform"/>) and to then apply flipping data for each character individually (using <see cref="MoveFlipped"/>).
/// </summary>
/// <param name="stringPos">The position that the string is drawn at.</param>
/// <param name="charPosOffset">The offset from the <paramref name="stringPos"/> that the current character is drawn at.</param>
/// <param name="rotation">The rotation to draw with.</param>
/// <param name="origin">The origin to subtract from the position.</param>
/// <param name="scale">The scale to draw with.</param>
/// <param name="effects">The flipping to draw with.</param>
/// <param name="stringSize">The size of the string, which is only used when <paramref name="effects"/> is not <see cref="SpriteEffects.None"/>.</param>
/// <param name="charSize">The size of the current character, which is only used when <paramref name="effects"/> is not <see cref="SpriteEffects.None"/>.</param>
/// <returns>The transformed final draw position.</returns>
public Vector2 TransformSingleCharacter(Vector2 stringPos, Vector2 charPosOffset, float rotation, Vector2 origin, Vector2 scale, SpriteEffects effects, Vector2 stringSize, Vector2 charSize) {
return Vector2.Transform(this.MoveFlipped(charPosOffset, effects, charSize), this.CalculateStringTransform(stringPos, rotation, origin, scale, effects, stringSize));
}
private Vector2 MeasureString(CodePointSource text, bool ignoreTrailingSpaces) {
var size = Vector2.Zero;
if (text.Length <= 0)
return size;
var xOffset = 0F;
var index = 0;
while (index < text.Length) {
var (codePoint, length) = text.GetCodePoint(index);
switch (codePoint) {
case '\n':
xOffset = 0;
size.Y += this.LineHeight;
break;
case GenericFont.Emsp:
xOffset += this.LineHeight;
break;
case GenericFont.Nbsp:
xOffset += this.MeasureCharacter(' ');
break;
case GenericFont.Zwsp:
// don't add width for a zero-width space
break;
case ' ':
if (ignoreTrailingSpaces && GenericFont.IsTrailingSpace(text, index)) {
// if this is a trailing space, we can skip remaining spaces too
index = text.Length - 1;
break;
}
xOffset += this.MeasureCharacter(' ');
break;
default:
xOffset += this.MeasureCharacter(codePoint);
break;
}
// increase x size if this line is the longest
if (xOffset > size.X)
size.X = xOffset;
index += length;
}
// include the last line's height too!
size.Y += this.LineHeight;
return size;
}
private void DrawString(SpriteBatch batch, CodePointSource text, Vector2 position, Color color, float rotation, Vector2 origin, Vector2 scale, SpriteEffects effects, float layerDepth) {
var flipSize = effects != SpriteEffects.None ? this.MeasureString(text, false) : Vector2.Zero;
var trans = this.CalculateStringTransform(position, rotation, origin, scale, effects, flipSize);
var offset = Vector2.Zero;
var index = 0;
while (index < text.Length) {
var (codePoint, length) = text.GetCodePoint(index);
if (codePoint == '\n') {
offset.X = 0;
offset.Y += this.LineHeight;
} else {
var character = CodePointSource.ToString(codePoint);
var charSize = this.MeasureString(character);
var charPos = Vector2.Transform(this.MoveFlipped(offset, effects, charSize), trans);
this.DrawCharacter(batch, codePoint, character, charPos, color, rotation, scale, effects, layerDepth);
offset.X += charSize.X;
}
index += length;
}
}
internal static IEnumerable<IEnumerable<string>> SplitStringSeparate(IEnumerable<DecoratedCodePointSource> text, float maxWidth, float scale) {
var currWidth = 0F;
var lastSpacePart = -1;
var lastSpaceIndex = -1;
var widthSinceLastSpace = 0F;
var curr = new StringBuilder();
var fullSplit = new List<List<string>>();
foreach (var part in text) {
var partSplit = new List<string>();
AddWidth(partSplit, part.ExtraWidth * scale, true);
var index = 0;
while (index < part.Source.Length) {
var (codePoint, length) = part.Source.GetCodePoint(index);
if (codePoint == '\n') {
// fake split at pre-defined new lines
curr.Append('\n');
lastSpacePart = -1;
lastSpaceIndex = -1;
widthSinceLastSpace = 0;
currWidth = 0;
} else {
var character = CodePointSource.ToString(codePoint);
var charWidth = part.Font.MeasureString(character).X * scale;
if (codePoint == ' ' || codePoint == GenericFont.Emsp || codePoint == GenericFont.Zwsp) {
// remember the location of this (breaking!) space
lastSpacePart = fullSplit.Count;
lastSpaceIndex = curr.Length;
widthSinceLastSpace = 0;
// we never want to insert a line break before a space!
AddWidth(partSplit, charWidth, false);
} else {
AddWidth(partSplit, charWidth, true);
}
curr.Append(character);
}
index += length;
}
if (curr.Length > 0) {
partSplit.Add(curr.ToString());
curr.Clear();
}
fullSplit.Add(partSplit);
}
return fullSplit;
void AddWidth(ICollection<string> partSplit, float width, bool canBreakHere) {
if (canBreakHere && currWidth + width >= maxWidth) {
// check if this line contains a space
if (lastSpaceIndex < 0) {
// if there is no last space, the word is longer than a line so we split here
partSplit.Add(curr.ToString());
curr.Clear();
currWidth = 0;
} else {
if (lastSpacePart < fullSplit.Count) {
// the last space exists, but isn't a part of curr, so we have to backtrack and split the previous token
var prevPart = fullSplit[lastSpacePart];
var prevCurr = prevPart[prevPart.Count - 1];
prevPart[prevPart.Count - 1] = prevCurr.Substring(0, lastSpaceIndex + 1);
prevPart.Add(prevCurr.Substring(lastSpaceIndex + 1));
} else {
// split after the last space
partSplit.Add(curr.ToString().Substring(0, lastSpaceIndex + 1));
curr.Remove(0, lastSpaceIndex + 1);
}
// we need to restore the width accumulated since the last space for the new line
currWidth = widthSinceLastSpace;
}
widthSinceLastSpace = 0;
lastSpacePart = -1;
lastSpaceIndex = -1;
}
currWidth += width;
widthSinceLastSpace += width;
}
}
internal static IEnumerable<StringBuilder> TruncateString(IEnumerable<DecoratedCodePointSource> text, float maxWidth, float scale, bool fromBack, string ellipsis) {
var total = new StringBuilder();
var extraWidth = 0F;
var endReached = false;
foreach (var part in fromBack ? text.Reverse() : text) {
var curr = new StringBuilder();
// if we reached the end previously, all the other parts should just be empty
if (!endReached) {
extraWidth += part.ExtraWidth * scale;
var index = 0;
while (index < part.Source.Length) {
var innerIndex = fromBack ? part.Source.Length - 1 - index : index;
var (codePoint, length) = part.Source.GetCodePoint(innerIndex, fromBack);
var character = CodePointSource.ToString(codePoint);
if (fromBack) {
curr.Insert(0, character);
total.Insert(0, character);
} else {
curr.Append(character);
total.Append(character);
}
if (part.Font.MeasureString(new CodePointSource(total + ellipsis), false).X * scale + extraWidth >= maxWidth) {
if (fromBack) {
curr.Remove(0, length).Insert(0, ellipsis);
total.Remove(0, length).Insert(0, ellipsis);
} else {
curr.Remove(curr.Length - length, length).Append(ellipsis);
total.Remove(total.Length - length, length).Append(ellipsis);
}
endReached = true;
break;
}
index += length;
}
}
yield return curr;
}
}
private static bool IsTrailingSpace(CodePointSource s, int index) {
while (index < s.Length) {
var (codePoint, length) = s.GetCodePoint(index);
if (codePoint != ' ')
return false;
index += length;
}
return true;
}
internal readonly struct DecoratedCodePointSource {
public readonly CodePointSource Source;
public readonly GenericFont Font;
public readonly float ExtraWidth;
public DecoratedCodePointSource(CodePointSource source, GenericFont font, float extraWidth) {
this.Source = source;
this.Font = font;
this.ExtraWidth = extraWidth;
}
}
}
}