optional<std::string> parseProperty(const char* name, const JSValue& value) {
if (std::string { "text-font" } == name) {
if (!value.IsArray()) {
Log::Warning(Event::ParseStyle, "value of '%s' must be an array of strings", name);
return {};
}
std::string result = "";
for (rapidjson::SizeType i = 0; i < value.Size(); ++i) {
const JSValue& stop = value[i];
if (stop.IsString()) {
result += stop.GetString();
if (i < value.Size()-1) {
result += ",";
}
} else {
Log::Warning(Event::ParseStyle, "text-font members must be strings");
return {};
}
}
return result;
}
if (!value.IsString()) {
Log::Warning(Event::ParseStyle, "value of '%s' must be a string", name);
return {};
}
return std::string { value.GetString(), value.GetStringLength() };
}
optional<RotateAnchorType> parseProperty<RotateAnchorType>(const char* name, const JSValue& value) {
if (!value.IsString()) {
Log::Warning(Event::ParseStyle, "value of '%s' must be a string", name);
return {};
}
return { RotateAnchorTypeClass({ value.GetString(), value.GetStringLength() }) };
}
optional<std::string> parseConstant(const char* name, const JSValue& value) {
if (!value.IsString()) {
Log::Warning(Event::ParseStyle, "value of '%s' must be a string", name);
return {};
}
return std::string { value.GetString(), value.GetStringLength() };
}
optional<LineCapType> parseConstant<LineCapType>(const char* name, const JSValue& value) {
if (!value.IsString()) {
Log::Warning(Event::ParseStyle, "value of '%s' must be a string", name);
return {};
}
return { LineCapTypeClass({ value.GetString(), value.GetStringLength() }) };
}
optional<Color> parseProperty(const char* name, const JSValue& value) {
if (!value.IsString()) {
Log::Warning(Event::ParseStyle, "value of '%s' must be a string", name);
return {};
}
CSSColorParser::Color css_color = CSSColorParser::parse({ value.GetString(), value.GetStringLength() });
// Premultiply the color.
const float factor = css_color.a / 255;
return Color{{(float)css_color.r * factor,
(float)css_color.g * factor,
(float)css_color.b * factor,
css_color.a}};
}