This removes all of the fixed-function particle affector classes.
Instead, each particle effect just has two SkSL snippets, one for
spawn logic, and one for update logic. Each one gets an inout copy
of the particle struct. Ultimately, this makes the effects much
simpler and smaller, while also being far more flexible (you can
do whatever you want with any values you want). Finally, because
the interpreter is vectorized and a particular effect's scripts
are usually tuned to the specific behaviors desired, it's faster
on basically every effect I compared.
I re-created all of the old effects in the new system. Many just
use pure SkSL (no curves or anything). Some of the old curve and
path/text stuff was very handy, though - so those are now exposed
as external values in the interpreter. Basically, an effect can
have any number of named "bindings" that are a callable thing.
This can be a path, text (shortcut for making fancy paths), curve,
or color curve. The path ones return a float4 with position and
normal, the curves return one or four floats.
... and this transposes all of the particle data storage into
SoA form, so that it can use the much faster interpreter entry
point.
Change-Id: Iebe711c45994c4201041b12d171af976bc5e758e
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/222057
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Mike Reed <reed@google.com>
Current strategy: everything from the top
Things to look at first are the manual changes:
- added tools/rewrite_includes.py
- removed -Idirectives from BUILD.gn
- various compile.sh simplifications
- tweak tools/embed_resources.py
- update gn/find_headers.py to write paths from the top
- update gn/gn_to_bp.py SkUserConfig.h layout
so that #include "include/config/SkUserConfig.h" always
gets the header we want.
No-Presubmit: true
Change-Id: I73a4b181654e0e38d229bc456c0d0854bae3363e
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/209706
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Hal Canary <halcanary@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Reviewed-by: Florin Malita <fmalita@chromium.org>
All curves (and path affectors) are driven by an SkParticleValue. The
value can derive its value from the current defaults (age of particle
or effect), or explicitly choose the other one, a random value, or any
other particle value. Values can be range adjusted and support repeat,
clamp, and mirror tiling.
Also fixed some more issues related to resource path in the slide GUI.
Bug: skia:
Change-Id: I4755018d5b57ae2d5ec400d541055ca4fb542978
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/196760
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
The other generator was never used (or useful). String-based serialization
of enums is quite helpful, though.
Bug: skia:
Change-Id: Ic9d58f8d20cfe7aba47722bd74f1e6f8f0f219e5
Reviewed-on: https://skia-review.googlesource.com/c/195368
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Move to a model that only needs floats, and puts the age in the
SkParticleState struct. Add a better test case for spawn affector
animation, to verify that things are still working.
Bug: skia:
Change-Id: I97d99de5f5d4cb302b76116e67ecc93368fb1677
Reviewed-on: https://skia-review.googlesource.com/c/193580
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
- Collapsed the per-particle data into a single struct, and
use that to communicate with drawables, too. Let the drawables
manage allocation of xforms, colors, etc. Helpful for non-atlas
drawables, and just to keep the effect code simpler.
- Having all of the params in a single struct allows us to move
the remaining animated behaviors into affectors (color/frame).
- Added SkColorCurve, which works like SkCurve for SkColor4f.
Use that to create a color affector (rather than simple
start/end colors in the effect params).
- Also put the stable random in SkParticleState. This is going
to be necessary if/when we change affectors to operate on all
particles (rather than one at a time). Still need to move t
value into the particle struct (or eval it from the lifetime
params on demand).
Change-Id: Icf39116acbfd5d6e8eb91e9affbd8898d106211d
Reviewed-on: https://skia-review.googlesource.com/c/193473
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
This adds a new "Particles" slide to viewer, that allows
editing, loading, and saving particle effects. All of the
particle system code is in modules/particles.
There are many rough edges and some not-yet-finished changes
to generalize the model[1]. A rough overview:
- SkReflected.h implements a lightweight reflection system
for classes derived from SkReflected. Adding a new class
involves deriving from SkReflected, adding a macro to the
class declaration, and implementing visitFields(), which
simply calls a virtual on an SkFieldVisitor for each field.
Currently, emitters and affectors use this mechanism.
- SkParticleSerialization.h demonstrates two useful field
visitors - for serializing to and from JSON. The driver
code that uses those is directly in ParticlesSlide.
- SkParticleData.h and SkCurve.h define a variety of helper
types for talking about particles, both for parameterizing
individual values, and communicating about the state of a
particle among the effect, affectors, and emitters.
- SkParticleEffect.h defines the static data definition of
an effect (SkParticleEffectParams), as well as a running
instance of an effect (SkParticleEffect). The effect has
simple update() and draw() methods.
- ParticlesSlide.cpp adds a third field visitor to generate
GUIs for interactively editing the running effect.
---
1: The critical change I'd like to make is to remove all
special case behavior over time and at spawn (setting sprite
frames, size over time, color over time, etc...). Integration
is the only fixed function behavior. Everything else is driven
by two lists of affectors. One is applied at spawn time, using
the effect's lifetime to evaluate curves. This allows spawning
particles with different colors as the effect ages out, for
example. The second list is applied every frame to update
existing particles, and is driven by the particle's lifetime.
This allows particles to change color after being spawned, for
example.
With a small set of affectors using a single expressive curve
primitive (keyframed list of cubic curve segments), we can
have affectors that update color, size, velocity, position,
sprite frame, etc., and implement many complex behaviors.
Bug: skia:
Change-Id: Id9402bef22825d55d021c5a2f9e5e41791aabaf4
Reviewed-on: https://skia-review.googlesource.com/c/181404
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Mike Reed <reed@google.com>