pyffi.formats.dds

102 """This class implements the DDS format.""" 103 xml_file_name = 'dds.xml' 104 # where to look for dds.xml and in what order: 105 # DDSXMLPATH env var, or DdsFormat module directory 106 xml_file_path = [os.getenv('DDSXMLPATH'), os.path.dirname(__file__)] 107 # file name regular expression match 108 RE_FILENAME = re.compile(r'^.*\.dds$', re.IGNORECASE) 109 # used for comparing floats 110 _EPSILON = 0.0001 111 112 # basic types 113 int = pyffi.object_models.common.Int 114 uint = pyffi.object_models.common.UInt 115 byte = pyffi.object_models.common.Byte 116 ubyte = pyffi.object_models.common.UByte 117 char = pyffi.object_models.common.Char 118 short = pyffi.object_models.common.Short 119 ushort = pyffi.object_models.common.UShort 120 float = pyffi.object_models.common.Float 121 PixelData = pyffi.object_models.common.UndecodedData 122 123 # implementation of dds-specific basic types 124

125 - class HeaderString(BasicBase):

126 """Basic type which implements the header of a DDS file."""

127 - def __init__(self, **kwargs):

128 BasicBase.__init__(self, **kwargs)

129

130 - def __str__(self):

131 return 'DDS'

132

133 - def get_detail_display(self):

134 return self.__str__()

135

136 - def get_hash(self, data=None):

137 """Return a hash value for this value. 138 139 :return: An immutable object that can be used as a hash. 140 """ 141 return None

142

143 - def read(self, stream, data):

144 """Read header string from stream and check it. 145 146 :param stream: The stream to read from. 147 :type stream: file 148 """ 149 hdrstr = stream.read(4) 150 # check if the string is correct 151 if hdrstr != "DDS ".encode("ascii"): 152 raise ValueError( 153 "invalid DDS header: expected 'DDS ' but got '%s'" % hdrstr)

154

155 - def write(self, stream, data):

156 """Write the header string to stream. 157 158 :param stream: The stream to write to. 159 :type stream: file 160 """ 161 stream.write("DDS ".encode("ascii"))

162

163 - def get_size(self, data=None):

164 """Return number of bytes the header string occupies in a file. 165 166 :return: Number of bytes. 167 """ 168 return 4

169 170 @staticmethod

171 - def version_number(version_str):

172 """Converts version string into an integer. 173 174 :param version_str: The version string. 175 :type version_str: str 176 :return: A version integer. 177 178 >>> hex(DdsFormat.version_number('DX10')) 179 '0xa000000' 180 """ 181 return {'DX9': 0x09000000, 'DX10': 0x0A000000}[version_str]

182

183 - class Data(pyffi.object_models.FileFormat.Data):

184 """A class to contain the actual dds data."""

185 - def __init__(self, version=0x09000000):

186 self.version = version 187 self.header = DdsFormat.Header() 188 self.pixeldata = DdsFormat.PixelData() 189 190 # TODO refactor xml model so we can get rid of these 191 self.user_version = 0 192 self.user_version2 = 0

193

194 - def inspect_quick(self, stream):

195 """Quickly checks if stream contains DDS data, and gets the 196 version, by looking at the first 8 bytes. 197 198 :param stream: The stream to inspect. 199 :type stream: file 200 """ 201 pos = stream.tell() 202 try: 203 hdrstr = stream.read(4) 204 if hdrstr != "DDS ".encode("ascii"): 205 raise ValueError("Not a DDS file.") 206 size = struct.unpack("<I", stream.read(4)) 207 if size == 124: 208 self.version = 0x09000000 # DX9 209 elif size == 144: 210 self.version = 0x0A000000 # DX10 211 finally: 212 stream.seek(pos)

213 214 # overriding pyffi.object_models.FileFormat.Data methods 215

216 - def inspect(self, stream):

217 """Quickly checks if stream contains DDS data, and reads the 218 header. 219 220 :param stream: The stream to inspect. 221 :type stream: file 222 """ 223 pos = stream.tell() 224 try: 225 self.inspect_quick(stream) 226 self.header.read(stream, data=self) 227 finally: 228 stream.seek(pos)

229 230

231 - def read(self, stream, verbose=0):

232 """Read a dds file. 233 234 :param stream: The stream from which to read. 235 :type stream: ``file`` 236 :param verbose: The level of verbosity. 237 :type verbose: ``int`` 238 """ 239 # read the file 240 self.inspect_quick(stream) 241 self.header.read(stream, data=self) 242 self.pixeldata.read(stream, data=self) 243 244 # check if we are at the end of the file 245 if stream.read(1): 246 raise ValueError( 247 'end of file not reached: corrupt dds file?')

248

249 - def write(self, stream, verbose=0):

250 """Write a dds file. 251 252 :param stream: The stream to which to write. 253 :type stream: ``file`` 254 :param verbose: The level of verbosity. 255 :type verbose: ``int`` 256 """ 257 # TODO: make sure pixel data has correct length 258 259 # write the file 260 # first header 261 self.header.write(stream, data=self) 262 # next the pixel data 263 self.pixeldata.write(stream, data=self)

264 265 # DetailNode 266

267 - def get_detail_child_nodes(self, edge_filter=EdgeFilter()):

268 return self.header.get_detail_child_nodes(edge_filter=edge_filter)

269

270 - def get_detail_child_names(self, edge_filter=EdgeFilter()):

271 return self.header.get_detail_child_names(edge_filter=edge_filter)

Source Code for Package pyffi.formats.dds