require "cache" --[[ TODO: all these functions should probably be methods on Face objects ]]-- function getGlyph(face, charcode) local hash = "glyph|"..face.hash.."|"..charcode local glyph = Cache:check(hash) if glyph then -- cache hit return glyph[1] end local rendered_glyph = face.ftface:renderGlyph(charcode) if not rendered_glyph then DEBUG("error rendering glyph (charcode=", charcode, ") for face", face) return end glyph = CacheItem:new{rendered_glyph} glyph.size = glyph[1].bb:getWidth() * glyph[1].bb:getHeight() / 2 + 32 Cache:insert(hash, glyph) return glyph[1] end function getSubTextByWidth(text, face, width, kerning) local pen_x = 0 local prevcharcode = 0 local char_list = {} for uchar in string.gfind(text, "([%z\1-\127\194-\244][\128-\191]*)") do if pen_x < width then local charcode = util.utf8charcode(uchar) local glyph = getGlyph(face, charcode) if kerning and prevcharcode then local kern = face.ftface:getKerning(prevcharcode, charcode) pen_x = pen_x + kern end pen_x = pen_x + glyph.ax if pen_x <= width then prevcharcode = charcode table.insert(char_list, uchar) else break end end end return table.concat(char_list) end function sizeUtf8Text(x, width, face, text, kerning) if not text then DEBUG("sizeUtf8Text called without text"); return end -- may still need more adaptive pen placement when kerning, -- see: http://freetype.org/freetype2/docs/glyphs/glyphs-4.html local pen_x = 0 local pen_y_top = 0 local pen_y_bottom = 0 local prevcharcode = 0 for uchar in string.gfind(text, "([%z\1-\127\194-\244][\128-\191]*)") do if pen_x < (width - x) then local charcode = util.utf8charcode(uchar) local glyph = getGlyph(face, charcode) if kerning and (prevcharcode ~= 0) then pen_x = pen_x + face.ftface:getKerning(prevcharcode, charcode) end pen_x = pen_x + glyph.ax pen_y_top = math.max(pen_y_top, glyph.t) pen_y_bottom = math.max(pen_y_bottom, glyph.bb:getHeight() - glyph.t) --DEBUG("ax:"..glyph.ax.." t:"..glyph.t.." r:"..glyph.r.." h:"..glyph.bb:getHeight().." w:"..glyph.bb:getWidth().." yt:"..pen_y_top.." yb:"..pen_y_bottom) prevcharcode = charcode end -- if pen_x < (width - x) end -- for uchar return { x = pen_x, y_top = pen_y_top, y_bottom = pen_y_bottom} end function renderUtf8Text(buffer, x, y, face, text, kerning) if not text then DEBUG("renderUtf8Text called without text"); return 0 end -- may still need more adaptive pen placement when kerning, -- see: http://freetype.org/freetype2/docs/glyphs/glyphs-4.html local pen_x = 0 local prevcharcode = 0 local buffer_width = buffer:getWidth() for uchar in string.gfind(text, "([%z\1-\127\194-\244][\128-\191]*)") do if pen_x < buffer_width then local charcode = util.utf8charcode(uchar) local glyph = getGlyph(face, charcode) if kerning and (prevcharcode ~= 0) then pen_x = pen_x + face.ftface:getKerning(prevcharcode, charcode) end buffer:addblitFrom( glyph.bb, x + pen_x + glyph.l, y - glyph.t, 0, 0, glyph.bb:getWidth(), glyph.bb:getHeight()) pen_x = pen_x + glyph.ax prevcharcode = charcode end -- if pen_x < buffer_width end -- for uchar return pen_x end