Truetype格式解析类

// ************************************************************************************* // TTF.cpp // // True type (*.ttf) and OpenType (*.otf) font loading/rendering implementation. // // Ryan Bogean // April 28, 2012 // // ************************************************************************************* #include "TTF.h" #include <vector> #include <map> #include <fstream> #include <algorithm> #include <limits> #include <utility> #include <cmath> #include <sstream> using namespace Utility; using namespace TTFCore; // --------------------------------------------------------------------------------------------------------------------------- // exceptions // --------------------------------------------------------------------------------------------------------------------------- // ----- FontException ----- FontException::FontException () : msg("Unknown error message.") {} FontException::FontException (const char* msg_) : msg(msg_) {} FontException::FontException (const std::string& msg_) : msg(msg_) {} const char* FontException::what() const throw() { return msg.c_str(); } // ----- FileFailure ----- FileFailure::FileFailure (const std::string& flnm) { std::stringstream ss; ss << "Unknown error reading file: '" << flnm << "'."; msg = ss.str(); } // ----- FileLengthError ----- FileLengthError::FileLengthError () : FontException("Length error reading memory mapped file, file has size of 0.") {} FileLengthError::FileLengthError (const std::string& flnm) { std::stringstream ss; ss << "Length error reading file: '" << flnm << "', file has size of 0."; msg = ss.str(); } // ----- TableDoesNotExist ----- TableDoesNotExist::TableDoesNotExist (const std::string& table) { std::stringstream ss; ss << "Cannot load font, '" << table << "' table does not exist."; msg = ss.str(); } // ----- ChecksumException ----- ChecksumException::ChecksumException (const std::string& table) { std::stringstream ss; ss << "Check sum error in '" << table << "'."; msg = ss.str(); } // ----- VersionException ----- VersionException::VersionException (const std::string& msg) : FontException(msg) {} // ----- InvalidFontException ----- InvalidFontException::InvalidFontException (const std::string& msg) : FontException(msg) {} // ----- UnsupportedCap ----- UnsupportedCap::UnsupportedCap (const std::string& msg) : FontException(msg) {} // --------------------------------------------------------------------------------------------------------------------------- // Simple math 'library' // --------------------------------------------------------------------------------------------------------------------------- // ----- vec2f ----- vec2f::vec2f () {} vec2f::vec2f (float x_, float y_) : x(x_), y(y_) {} bool vec2f::operator== (vec2f v) const { return x == v.x && y == v.y; } bool vec2f::operator!= (vec2f v) const { return x != v.x || y != v.y; } vec2f& vec2f::operator+= (vec2f v) { x += v.x; y += v.y; return *this; } vec2f& vec2f::operator-= (vec2f v) { x -= v.x; y -= v.y; return *this; } vec2f& vec2f::operator*= (vec2f v) { x *= v.x; y *= v.y; return *this; } vec2f& vec2f::operator/= (vec2f v) { x /= v.x; y /= v.y; return *this; } vec2f& vec2f::operator+= (float f) { x += f; y += f; return *this; } vec2f& vec2f::operator-= (float f) { x -= f; y -= f; return *this; } vec2f& vec2f::operator*= (float f) { x *= f; y *= f; return *this; } vec2f& vec2f::operator/= (float f) { x /= f; y /= f; return *this; } vec2f Utility::TTFCore::operator+ (vec2f v0, vec2f v1) { return vec2f(v0.x + v1.x, v0.y + v1.y); } vec2f Utility::TTFCore::operator- (vec2f v0, vec2f v1) { return vec2f(v0.x - v1.x, v0.y - v1.y); } vec2f Utility::TTFCore::operator* (vec2f v0, vec2f v1) { return vec2f(v0.x * v1.x, v0.y * v1.y); } vec2f Utility::TTFCore::operator/ (vec2f v0, vec2f v1) { return vec2f(v0.x / v1.x, v0.y / v1.y); } vec2f Utility::TTFCore::operator+ (float f, vec2f v1) { return vec2f(f + v1.x, f + v1.y); } vec2f Utility::TTFCore::operator- (float f, vec2f v1) { return vec2f(f - v1.x, f - v1.y); } vec2f Utility::TTFCore::operator* (float f, vec2f v1) { return vec2f(f * v1.x, f * v1.y); } vec2f Utility::TTFCore::operator/ (float f, vec2f v1) { return vec2f(f / v1.x, f / v1.y); } vec2f Utility::TTFCore::operator+ (vec2f v0, float f) { return vec2f(v0.x + f, v0.y + f); } vec2f Utility::TTFCore::operator- (vec2f v0, float f) { return vec2f(v0.x - f, v0.y - f); } vec2f Utility::TTFCore::operator* (vec2f v0, float f) { return vec2f(v0.x * f, v0.y * f); } vec2f Utility::TTFCore::operator/ (vec2f v0, float f) { return vec2f(v0.x / f, v0.y / f); } float Utility::TTFCore::dot (vec2f v0, vec2f v1) { return (v0.x*v1.x) + (v0.y*v1.y); } float Utility::TTFCore::cross (vec2f v0, vec2f v1) { return (v0.x*v1.y) - (v0.y*v1.x); } // ----- matrix3x2f ----- matrix3x2f::matrix3x2f () : a(1.0f), b(0.0f), c(0.0f), d(1.0f), e(0.0f), f(0.0f) {} vec2f Utility::TTFCore::mul (vec2f v, const matrix3x2f& m) { // obviously you can't multiply a 2d vector with a 3x2 matrix // in this case we 'extend' the 2d vector to a 3d vector by appending 1.0f // course this need'nt be done explicitly return vec2f( v.x*m.a + v.y*m.c + m.e , v.x*m.b + v.y*m.d + m.f ); } vec2f Utility::TTFCore::normal (vec2f v) { return v / std::sqrt(dot(v,v)); } // ----- vec4f ----- vec4f::vec4f () {} vec4f::vec4f (float x_, float y_, float z_, float w_) : x(x_), y(y_), z(z_), w(w_) {} // --------------------------------------------------------------------------------------------------------------------------- // Triangulator // --------------------------------------------------------------------------------------------------------------------------- // ----- Triangulator internal types ----- ContourPoint::ContourPoint () { endPoint = false; flags = 0; pos = vec2f(0,0); } bool ContourPoint::OnCurve () const { return (flags & 1) != 0; } bool ContourPoint::XShortVector () const { return (flags & 2) != 0; } bool ContourPoint::YShortVector () const { return (flags & 4) != 0; } bool ContourPoint::XIsSame () const { return (flags & 16) != 0; } bool ContourPoint::XIsDifferent () const { return (flags & 16) == 0; } bool ContourPoint::XIsPositive () const { return (flags & 16) != 0; } bool ContourPoint::XIsNegative () const { return (flags & 16) == 0; } bool ContourPoint::YIsSame () const { return (flags & 32) != 0; } bool ContourPoint::YIsDifferent () const { return (flags & 32) == 0; } bool ContourPoint::YIsPositive () const { return (flags & 32) != 0; } bool ContourPoint::YIsNegative () const { return (flags & 32) == 0; } Triangle::Triangle (size_t v0_, size_t v1_, size_t v2_, char coef_) { v0 = v0_; v1 = v1_; v2 = v2_; coef = coef_; } Edge::Edge (size_t v0_, size_t v1_) { v0 = v0_; v1 = v1_; } LineSegment::LineSegment (size_t v0_, size_t v1_, float length_) { v0 = v0_; v1 = v1_; length = length_; } Bound::Bound (vec2f p_, vec2f d_) : p(p_), d(d_) {} TriEdge::TriEdge (size_t v0_, size_t v1_) : v0(v0_), v1(v1_), inUse(true) {} void Mesh::Clear () { verts.clear(); } std::vector<MeshVertex>::iterator Mesh::begin () { return verts.begin(); } std::vector<MeshVertex>::const_iterator Mesh::begin () const { return verts.begin(); } std::vector<MeshVertex>::iterator Mesh::end () { return verts.end(); } std::vector<MeshVertex>::const_iterator Mesh::end () const { return verts.end(); } // ----- internal helper functions ----- void Triangulator::ClearCache () { verts.clear(); edges.clear(); tris.clear(); seg.clear(); bounds.cle