Flat and Square caps are implemented.
Bevel joins are implemented.
Round caps, Round joins and Miter joins are left for another PR.
Signed-off-by: Sebastien Binet <s@sbinet.org>
This is a first step towards supporting affine drawing transforms.
The rendering algorithm relies on quadratic curves that do not cross
x = 0 more than once, thus curves must be split after any rotation/shear
transforms. Move this logic and the generation of vertices to package gpu.
Also close all curves and draw zero-width edges as preparation for
transform since the will no longer implicitly be vertical with no
effect.
This commit will severely affect performance since vertexes are now
transformed also for cached items, using cpu resources.
Signed-off-by: Viktor <viktor.ogeman@gmail.com>
Converting
macro := op.Record(ops)
...
macro.Stop()
macro.Add()
to
macro := op.Record(ops)
...
call := macro.Stop()
call.Add(ops)
Which is more general (call.Add can take a different ops than the op.Record
that started it), and enforced the order between Stop and the subsequent Add.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The funcs replace stack.Push and macro.Record, which become private.
This makes stack and macro faster to write, in particular for stacks
where you can just write the following line to save and restore the
state :
defer op.Push(ops).Pop()
This usage requires Push to return a pointer (since Pop has a pointer
receiver), or else the code doesn't compile.
For consistancy, I tried to do the same for op.Record, but this implied
to turn all the MacroOp fields into pointers, and this caused some
panics. As a result, op.Record doesn't return a pointer.
An other side effect pointed by Larry Clapp: StackOp and MacroOp are not
re-usable any more, you have to allocate a new one for each usage, using
the described funcs above.
Signed-off-by: Thomas Bruyelle <thomas.bruyelle@gmail.com>
The ability to invoke other operation lists belongs in the new CallOp.
While we're here, make MacroOp.Add use a pointer receiver to match the
other methods.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Remembering the order of the corners in the RoundRect is difficult,
which suggest that RoundRect should be a struct with named fields.
Do that, and make Rect the special case where corner radii are all
zero.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Sebastien Binet