SFML/src/SFML/Graphics/Text.cpp

630 lines
21 KiB
C++

////////////////////////////////////////////////////////////
//
// SFML - Simple and Fast Multimedia Library
// Copyright (C) 2007-2019 Laurent Gomila (laurent@sfml-dev.org)
//
// This software is provided 'as-is', without any express or implied warranty.
// In no event will the authors be held liable for any damages arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it freely,
// subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented;
// you must not claim that you wrote the original software.
// If you use this software in a product, an acknowledgment
// in the product documentation would be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such,
// and must not be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source distribution.
//
////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////
// Headers
////////////////////////////////////////////////////////////
#include <SFML/Graphics/Text.hpp>
#include <SFML/Graphics/Texture.hpp>
#include <SFML/Graphics/RenderTarget.hpp>
#include <cmath>
namespace
{
// Add an underline or strikethrough line to the vertex array
void addLine(sf::VertexArray& vertices, float lineLength, float lineTop, const sf::Color& color, float offset, float thickness, float outlineThickness = 0)
{
float top = std::floor(lineTop + offset - (thickness / 2) + 0.5f);
float bottom = top + std::floor(thickness + 0.5f);
vertices.append(sf::Vertex(sf::Vector2f(-outlineThickness, top - outlineThickness), color, sf::Vector2f(1, 1)));
vertices.append(sf::Vertex(sf::Vector2f(lineLength + outlineThickness, top - outlineThickness), color, sf::Vector2f(1, 1)));
vertices.append(sf::Vertex(sf::Vector2f(-outlineThickness, bottom + outlineThickness), color, sf::Vector2f(1, 1)));
vertices.append(sf::Vertex(sf::Vector2f(-outlineThickness, bottom + outlineThickness), color, sf::Vector2f(1, 1)));
vertices.append(sf::Vertex(sf::Vector2f(lineLength + outlineThickness, top - outlineThickness), color, sf::Vector2f(1, 1)));
vertices.append(sf::Vertex(sf::Vector2f(lineLength + outlineThickness, bottom + outlineThickness), color, sf::Vector2f(1, 1)));
}
// Add a glyph quad to the vertex array
void addGlyphQuad(sf::VertexArray& vertices, sf::Vector2f position, const sf::Color& color, const sf::Glyph& glyph, float italicShear, float outlineThickness = 0)
{
float padding = 1.0;
float left = glyph.bounds.left - padding;
float top = glyph.bounds.top - padding;
float right = glyph.bounds.left + glyph.bounds.width + padding;
float bottom = glyph.bounds.top + glyph.bounds.height + padding;
float u1 = static_cast<float>(glyph.textureRect.left) - padding;
float v1 = static_cast<float>(glyph.textureRect.top) - padding;
float u2 = static_cast<float>(glyph.textureRect.left + glyph.textureRect.width) + padding;
float v2 = static_cast<float>(glyph.textureRect.top + glyph.textureRect.height) + padding;
vertices.append(sf::Vertex(sf::Vector2f(position.x + left - italicShear * top - outlineThickness, position.y + top - outlineThickness), color, sf::Vector2f(u1, v1)));
vertices.append(sf::Vertex(sf::Vector2f(position.x + right - italicShear * top - outlineThickness, position.y + top - outlineThickness), color, sf::Vector2f(u2, v1)));
vertices.append(sf::Vertex(sf::Vector2f(position.x + left - italicShear * bottom - outlineThickness, position.y + bottom - outlineThickness), color, sf::Vector2f(u1, v2)));
vertices.append(sf::Vertex(sf::Vector2f(position.x + left - italicShear * bottom - outlineThickness, position.y + bottom - outlineThickness), color, sf::Vector2f(u1, v2)));
vertices.append(sf::Vertex(sf::Vector2f(position.x + right - italicShear * top - outlineThickness, position.y + top - outlineThickness), color, sf::Vector2f(u2, v1)));
vertices.append(sf::Vertex(sf::Vector2f(position.x + right - italicShear * bottom - outlineThickness, position.y + bottom - outlineThickness), color, sf::Vector2f(u2, v2)));
}
}
namespace sf
{
////////////////////////////////////////////////////////////
Text::Text() :
m_string (),
m_font (NULL),
m_characterSize (30),
m_letterSpacingFactor (1.f),
m_lineSpacingFactor (1.f),
m_style (Regular),
m_fillColor (255, 255, 255),
m_outlineColor (0, 0, 0),
m_outlineThickness (0),
m_vertices (Triangles),
m_outlineVertices (Triangles),
m_verticesBuffer (Triangles, VertexBuffer::Static),
m_outlineVerticesBuffer(Triangles, VertexBuffer::Static),
m_bounds (),
m_geometryNeedUpdate (false),
m_fontTextureId (0)
{
}
////////////////////////////////////////////////////////////
Text::Text(const String& string, const Font& font, unsigned int characterSize) :
m_string (string),
m_font (&font),
m_characterSize (characterSize),
m_letterSpacingFactor (1.f),
m_lineSpacingFactor (1.f),
m_style (Regular),
m_fillColor (255, 255, 255),
m_outlineColor (0, 0, 0),
m_outlineThickness (0),
m_vertices (Triangles),
m_outlineVertices (Triangles),
m_verticesBuffer (Triangles, VertexBuffer::Static),
m_outlineVerticesBuffer(Triangles, VertexBuffer::Static),
m_bounds (),
m_geometryNeedUpdate (true),
m_fontTextureId (0)
{
}
////////////////////////////////////////////////////////////
void Text::setString(const String& string)
{
if (m_string != string)
{
m_string = string;
m_geometryNeedUpdate = true;
}
}
////////////////////////////////////////////////////////////
void Text::setFont(const Font& font)
{
if (m_font != &font)
{
m_font = &font;
m_geometryNeedUpdate = true;
}
}
////////////////////////////////////////////////////////////
void Text::setCharacterSize(unsigned int size)
{
if (m_characterSize != size)
{
m_characterSize = size;
m_geometryNeedUpdate = true;
}
}
////////////////////////////////////////////////////////////
void Text::setLetterSpacing(float spacingFactor)
{
if (m_letterSpacingFactor != spacingFactor)
{
m_letterSpacingFactor = spacingFactor;
m_geometryNeedUpdate = true;
}
}
////////////////////////////////////////////////////////////
void Text::setLineSpacing(float spacingFactor)
{
if (m_lineSpacingFactor != spacingFactor)
{
m_lineSpacingFactor = spacingFactor;
m_geometryNeedUpdate = true;
}
}
////////////////////////////////////////////////////////////
void Text::setStyle(Uint32 style)
{
if (m_style != style)
{
m_style = style;
m_geometryNeedUpdate = true;
}
}
////////////////////////////////////////////////////////////
void Text::setColor(const Color& color)
{
setFillColor(color);
}
////////////////////////////////////////////////////////////
void Text::setFillColor(const Color& color)
{
if (color != m_fillColor)
{
m_fillColor = color;
// Change vertex colors directly, no need to update whole geometry
// (if geometry is updated anyway, we can skip this step)
if (!m_geometryNeedUpdate)
{
for (std::size_t i = 0; i < m_vertices.getVertexCount(); ++i)
m_vertices[i].color = m_fillColor;
if (VertexBuffer::isAvailable())
{
if (m_verticesBuffer.getVertexCount() != m_vertices.getVertexCount())
m_verticesBuffer.create(m_vertices.getVertexCount());
m_verticesBuffer.update(&m_vertices[0]);
}
}
}
}
////////////////////////////////////////////////////////////
void Text::setOutlineColor(const Color& color)
{
if (color != m_outlineColor)
{
m_outlineColor = color;
// Change vertex colors directly, no need to update whole geometry
// (if geometry is updated anyway, we can skip this step)
if (!m_geometryNeedUpdate)
{
for (std::size_t i = 0; i < m_outlineVertices.getVertexCount(); ++i)
m_outlineVertices[i].color = m_outlineColor;
if (VertexBuffer::isAvailable())
{
if (m_outlineVerticesBuffer.getVertexCount() != m_outlineVertices.getVertexCount())
m_outlineVerticesBuffer.create(m_outlineVertices.getVertexCount());
m_outlineVerticesBuffer.update(&m_outlineVertices[0]);
}
}
}
}
////////////////////////////////////////////////////////////
void Text::setOutlineThickness(float thickness)
{
if (thickness != m_outlineThickness)
{
m_outlineThickness = thickness;
m_geometryNeedUpdate = true;
}
}
////////////////////////////////////////////////////////////
const String& Text::getString() const
{
return m_string;
}
////////////////////////////////////////////////////////////
const Font* Text::getFont() const
{
return m_font;
}
////////////////////////////////////////////////////////////
unsigned int Text::getCharacterSize() const
{
return m_characterSize;
}
////////////////////////////////////////////////////////////
float Text::getLetterSpacing() const
{
return m_letterSpacingFactor;
}
////////////////////////////////////////////////////////////
float Text::getLineSpacing() const
{
return m_lineSpacingFactor;
}
////////////////////////////////////////////////////////////
Uint32 Text::getStyle() const
{
return m_style;
}
////////////////////////////////////////////////////////////
const Color& Text::getColor() const
{
return getFillColor();
}
////////////////////////////////////////////////////////////
const Color& Text::getFillColor() const
{
return m_fillColor;
}
////////////////////////////////////////////////////////////
const Color& Text::getOutlineColor() const
{
return m_outlineColor;
}
////////////////////////////////////////////////////////////
float Text::getOutlineThickness() const
{
return m_outlineThickness;
}
////////////////////////////////////////////////////////////
Vector2f Text::findCharacterPos(std::size_t index) const
{
// Make sure that we have a valid font
if (!m_font)
return Vector2f();
// Adjust the index if it's out of range
if (index > m_string.getSize())
index = m_string.getSize();
// Precompute the variables needed by the algorithm
bool isBold = m_style & Bold;
float whitespaceWidth = m_font->getGlyph(L' ', m_characterSize, isBold).advance;
float letterSpacing = ( whitespaceWidth / 3.f ) * ( m_letterSpacingFactor - 1.f );
whitespaceWidth += letterSpacing;
float lineSpacing = m_font->getLineSpacing(m_characterSize) * m_lineSpacingFactor;
// Compute the position
Vector2f position;
Uint32 prevChar = 0;
for (std::size_t i = 0; i < index; ++i)
{
Uint32 curChar = m_string[i];
// Apply the kerning offset
position.x += m_font->getKerning(prevChar, curChar, m_characterSize);
prevChar = curChar;
// Handle special characters
switch (curChar)
{
case ' ': position.x += whitespaceWidth; continue;
case '\t': position.x += whitespaceWidth * 4; continue;
case '\n': position.y += lineSpacing; position.x = 0; continue;
}
// For regular characters, add the advance offset of the glyph
position.x += m_font->getGlyph(curChar, m_characterSize, isBold).advance + letterSpacing;
}
// Transform the position to global coordinates
position = getTransform().transformPoint(position);
return position;
}
////////////////////////////////////////////////////////////
FloatRect Text::getLocalBounds() const
{
ensureGeometryUpdate();
return m_bounds;
}
////////////////////////////////////////////////////////////
FloatRect Text::getGlobalBounds() const
{
return getTransform().transformRect(getLocalBounds());
}
////////////////////////////////////////////////////////////
void Text::draw(RenderTarget& target, RenderStates states) const
{
if (m_font)
{
ensureGeometryUpdate();
states.transform *= getTransform();
states.texture = &m_font->getTexture(m_characterSize);
// Only draw the outline if there is something to draw
if (m_outlineThickness != 0)
{
if (VertexBuffer::isAvailable())
{
target.draw(m_outlineVerticesBuffer, states);
}
else
{
target.draw(m_outlineVertices, states);
}
}
if (VertexBuffer::isAvailable())
{
target.draw(m_verticesBuffer, states);
}
else
{
target.draw(m_vertices, states);
}
}
}
////////////////////////////////////////////////////////////
void Text::ensureGeometryUpdate() const
{
if (!m_font)
return;
// Do nothing, if geometry has not changed and the font texture has not changed
if (!m_geometryNeedUpdate && m_font->getTexture(m_characterSize).m_cacheId == m_fontTextureId)
return;
// Save the current fonts texture id
m_fontTextureId = m_font->getTexture(m_characterSize).m_cacheId;
// Mark geometry as updated
m_geometryNeedUpdate = false;
// Clear the previous geometry
m_vertices.clear();
m_outlineVertices.clear();
m_bounds = FloatRect();
// No text: nothing to draw
if (m_string.isEmpty())
{
if (VertexBuffer::isAvailable())
{
if (m_verticesBuffer.getVertexCount())
m_verticesBuffer.create(0);
if (m_outlineVerticesBuffer.getVertexCount())
m_outlineVerticesBuffer.create(0);
}
return;
}
// Compute values related to the text style
bool isBold = m_style & Bold;
bool isUnderlined = m_style & Underlined;
bool isStrikeThrough = m_style & StrikeThrough;
float italicShear = (m_style & Italic) ? 0.209f : 0.f; // 12 degrees in radians
float underlineOffset = m_font->getUnderlinePosition(m_characterSize);
float underlineThickness = m_font->getUnderlineThickness(m_characterSize);
// Compute the location of the strike through dynamically
// We use the center point of the lowercase 'x' glyph as the reference
// We reuse the underline thickness as the thickness of the strike through as well
FloatRect xBounds = m_font->getGlyph(L'x', m_characterSize, isBold).bounds;
float strikeThroughOffset = xBounds.top + xBounds.height / 2.f;
// Precompute the variables needed by the algorithm
float whitespaceWidth = m_font->getGlyph(L' ', m_characterSize, isBold).advance;
float letterSpacing = ( whitespaceWidth / 3.f ) * ( m_letterSpacingFactor - 1.f );
whitespaceWidth += letterSpacing;
float lineSpacing = m_font->getLineSpacing(m_characterSize) * m_lineSpacingFactor;
float x = 0.f;
float y = static_cast<float>(m_characterSize);
// Create one quad for each character
float minX = static_cast<float>(m_characterSize);
float minY = static_cast<float>(m_characterSize);
float maxX = 0.f;
float maxY = 0.f;
Uint32 prevChar = 0;
for (std::size_t i = 0; i < m_string.getSize(); ++i)
{
Uint32 curChar = m_string[i];
// Skip the \r char to avoid weird graphical issues
if (curChar == '\r')
continue;
// Apply the kerning offset
x += m_font->getKerning(prevChar, curChar, m_characterSize);
// If we're using the underlined style and there's a new line, draw a line
if (isUnderlined && (curChar == L'\n' && prevChar != L'\n'))
{
addLine(m_vertices, x, y, m_fillColor, underlineOffset, underlineThickness);
if (m_outlineThickness != 0)
addLine(m_outlineVertices, x, y, m_outlineColor, underlineOffset, underlineThickness, m_outlineThickness);
}
// If we're using the strike through style and there's a new line, draw a line across all characters
if (isStrikeThrough && (curChar == L'\n' && prevChar != L'\n'))
{
addLine(m_vertices, x, y, m_fillColor, strikeThroughOffset, underlineThickness);
if (m_outlineThickness != 0)
addLine(m_outlineVertices, x, y, m_outlineColor, strikeThroughOffset, underlineThickness, m_outlineThickness);
}
prevChar = curChar;
// Handle special characters
if ((curChar == L' ') || (curChar == L'\n') || (curChar == L'\t'))
{
// Update the current bounds (min coordinates)
minX = std::min(minX, x);
minY = std::min(minY, y);
switch (curChar)
{
case L' ': x += whitespaceWidth; break;
case L'\t': x += whitespaceWidth * 4; break;
case L'\n': y += lineSpacing; x = 0; break;
}
// Update the current bounds (max coordinates)
maxX = std::max(maxX, x);
maxY = std::max(maxY, y);
// Next glyph, no need to create a quad for whitespace
continue;
}
// Apply the outline
if (m_outlineThickness != 0)
{
const Glyph& glyph = m_font->getGlyph(curChar, m_characterSize, isBold, m_outlineThickness);
float left = glyph.bounds.left;
float top = glyph.bounds.top;
float right = glyph.bounds.left + glyph.bounds.width;
float bottom = glyph.bounds.top + glyph.bounds.height;
// Add the outline glyph to the vertices
addGlyphQuad(m_outlineVertices, Vector2f(x, y), m_outlineColor, glyph, italicShear, m_outlineThickness);
// Update the current bounds with the outlined glyph bounds
minX = std::min(minX, x + left - italicShear * bottom - m_outlineThickness);
maxX = std::max(maxX, x + right - italicShear * top - m_outlineThickness);
minY = std::min(minY, y + top - m_outlineThickness);
maxY = std::max(maxY, y + bottom - m_outlineThickness);
}
// Extract the current glyph's description
const Glyph& glyph = m_font->getGlyph(curChar, m_characterSize, isBold);
// Add the glyph to the vertices
addGlyphQuad(m_vertices, Vector2f(x, y), m_fillColor, glyph, italicShear);
// Update the current bounds with the non outlined glyph bounds
if (m_outlineThickness == 0)
{
float left = glyph.bounds.left;
float top = glyph.bounds.top;
float right = glyph.bounds.left + glyph.bounds.width;
float bottom = glyph.bounds.top + glyph.bounds.height;
minX = std::min(minX, x + left - italicShear * bottom);
maxX = std::max(maxX, x + right - italicShear * top);
minY = std::min(minY, y + top);
maxY = std::max(maxY, y + bottom);
}
// Advance to the next character
x += glyph.advance + letterSpacing;
}
// If we're using the underlined style, add the last line
if (isUnderlined && (x > 0))
{
addLine(m_vertices, x, y, m_fillColor, underlineOffset, underlineThickness);
if (m_outlineThickness != 0)
addLine(m_outlineVertices, x, y, m_outlineColor, underlineOffset, underlineThickness, m_outlineThickness);
}
// If we're using the strike through style, add the last line across all characters
if (isStrikeThrough && (x > 0))
{
addLine(m_vertices, x, y, m_fillColor, strikeThroughOffset, underlineThickness);
if (m_outlineThickness != 0)
addLine(m_outlineVertices, x, y, m_outlineColor, strikeThroughOffset, underlineThickness, m_outlineThickness);
}
// Update the bounding rectangle
m_bounds.left = minX;
m_bounds.top = minY;
m_bounds.width = maxX - minX;
m_bounds.height = maxY - minY;
// Update the vertex buffer if it is being used
if (VertexBuffer::isAvailable())
{
if (m_verticesBuffer.getVertexCount() != m_vertices.getVertexCount())
m_verticesBuffer.create(m_vertices.getVertexCount());
m_verticesBuffer.update(&m_vertices[0]);
if (m_outlineVerticesBuffer.getVertexCount() != m_outlineVertices.getVertexCount())
m_outlineVerticesBuffer.create(m_outlineVertices.getVertexCount());
m_outlineVerticesBuffer.update(&m_outlineVertices[0]);
}
}
} // namespace sf