/// Format of the bit-packed rectangle is:
///
/// bits | name | description
/// ------+-------+-------------------------
/// 5 | nbits | number of bits used in subsequent values
/// nbits | xmin | minimum X value
/// nbits | xmax | maximum X value
/// nbits | ymin | minimum Y value
/// nbits | ymax | maximum Y value
///
/// If max values are less then min values the SWF is malformed;
/// in this case this method will raise an swf_error and set the
/// rectangle to the NULL rectangle. See is_null().
SWFRect
readRect(SWFStream& in)
{
in.align();
in.ensureBits(5);
const int nbits = in.read_uint(5);
int minx = 0, maxx = 0, miny = 0, maxy = 0;
if (nbits > 0) {
in.ensureBits(nbits*4);
minx = in.read_sint(nbits);
maxx = in.read_sint(nbits);
miny = in.read_sint(nbits);
maxy = in.read_sint(nbits);
}
// Check if this SWFRect is valid.
if (maxx < minx || maxy < miny) {
// We set invalid rectangles to NULL, but we might instead
// want to actually swap the values if the proprietary player
// does so. TODO: check it out.
IF_VERBOSE_MALFORMED_SWF(
log_swferror(_("Invalid rectangle: "
"minx=%g maxx=%g miny=%g maxy=%g"), minx, maxx, miny, maxy);
);
SWFMatrix
readSWFMatrix(SWFStream& in)
{
in.align();
in.ensureBits(1);
const bool has_scale = in.read_bit();
std::int32_t sx = 65536;
std::int32_t sy = 65536;
if (has_scale) {
in.ensureBits(5);
const std::uint8_t scale_nbits = in.read_uint(5);
if (scale_nbits) {
in.ensureBits(scale_nbits * 2);
sx = in.read_sint(scale_nbits);
sy = in.read_sint(scale_nbits);
}
}
in.ensureBits(1);
const bool has_rotate = in.read_bit();
std::int32_t shx = 0;
std::int32_t shy = 0;
if (has_rotate) {
in.ensureBits(5);
unsigned int rotate_nbits = in.read_uint(5);
if (rotate_nbits) {
in.ensureBits(rotate_nbits * 2);
shx = in.read_sint(rotate_nbits);
shy = in.read_sint(rotate_nbits);
}
}
in.ensureBits(5);
const std::uint8_t translate_nbits = in.read_uint(5);
std::int32_t tx = 0;
std::int32_t ty = 0;
if (translate_nbits) {
in.ensureBits(translate_nbits * 2);
tx = in.read_sint(translate_nbits);
ty = in.read_sint(translate_nbits);
}
return SWFMatrix(sx, shx, shy, sy, tx, ty);
}
