railway 0.3.2

Binary file format for vector animated pictures
Documentation 
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FMT

u32: unsigned integer on four bytes in big-endian order
f32: IEEE 754 number on four bytes in big endian order
step_type:
    0 = arc
    1 = cubic bezier curve
    2 = quadratic bezier curve
    3 = linear bezier curve (straight line)

u32   magic

---- virtual machine part below ----

u32   # of arguments
      arguments:
u32       string_section_offset
f32       x_default_value
f32       y_default_value
f32       x_range_min
f32       x_range_max
f32       y_range_min
f32       y_range_max

u32   # of instructions
      instructions:
u32       operation
u32       op1_addr
u32       op2_addr
u32       op3_addr

u32   # of outputs
      outputs:
u32       string_section_offset
u32       addr

---- rendering part below ----

u32   # of triangles
      triangles:
u32       p1_addr
u32       p2_addr
u32       p3_addr
u32       p1_rg_addr
u32       p1_ba_addr
u32       p2_rg_addr
u32       p2_ba_addr
u32       p3_rg_addr
u32       p3_ba_addr

u32   # of arcs
      arcs:
u32       start_point_addr
u32       center_addr
u32       deltas_addr

u32   # of cubic bezier curves
      bezier curves:
u32       p1_addr
u32       p2_addr
u32       p3_addr
u32       p4_addr

u32   # of quadratic bezier curves
      quadratic curves:
u32       p1_addr
u32       p2_addr
u32       p3_addr

u32   # of lines
      lines:
u32       p1_addr
u32       p2_addr

u32   # of strokers
      strokers:
u32       pattern_addr (p.x = dash length, p.y = gap length)
u32       width_addr (width = p.x + p.y)
u32       rg_addr
u32       ba_addr

u32   # of steps
      steps:
u32       step_type
u32       index

u32   # of paths
      paths:
u32       first_step
u32       length

u32   # of triangle_indexes
      triangle_indexes:
u32       triangle

u32   # of backgrounds
      backgrounds:
u32       first_triangle
u32       length

u32   # of rendering steps
      rendering steps:
u32       clip_or_stroke (0 or 1)
u32       path_index
          if clip_or_stroke == 0:
u32           background_index
          if clip_or_stroke == 1:
u32           stroker_index

---- strings below ----

u32   # of string bytes
      string bytes:
 u8       utf8_byte or null_byte