Test for viewer capibility to handle the basics of the 'tref' element and its attributes. Basic referencing is tested, as well as the equivalence of 'tref' to 'tspan' in attributes handling. There are six sub-tests.

The first box down from the top should contain green "Internal referenced text.", which is obtained by a 'tref' element reference to a 'text' element in a 'defs' section of this test file. The second box down from the top should contain red "External referenced text.", which is obtained by a 'tref' element reference to a 'text' element in a 'defs' section of an external file (auxiliary file to this test file).

The third box from the top tests changing of visual properties of 'tref' substrings. It should contain the string "Change color within string.", blue except for the single word "color" in red. Three 'tref' elements within the 'text' element each point to a substring in the 'defs' section of this test file -- the second 'tref' sets fill color to red and the others set fill color to blue.

The fourth box from the top tests that the x,y attributes of 'tref' behave like those of 'tspan'. The string "Bouncing up and down." is formed by four 'tref' elements pointing to 'text' elements in the 'defs' section, and each 'tref' is individually positions by the x,y attributes. The fifth box from the top tests an x-coordinate list in a 'tref', which individually places each character of the string "Char-by-char." The string is in a single 'text' element in the 'defs' section.

The final sub-test actually involves the single-line test description at the very top. It is written initially in blue, and then at the end is over-written in black by a 'tref' pointing to the 'desc' element of the test.

The rendered picture should match the reference image, except that some color "fuzziness" in the top line may result from anti-aliasing. Also, variations are possible in the text fonts and layout (per CSS2 rules).

The test also uses the 'rect' element, as well as basic fill (solid primary colors), stroke (black 1-pixel lines), font-family (Helvetica) and font-size properties.