Add SkParticleValue to allow further customization of curve behavior
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>
diff --git a/modules/particles/include/SkCurve.h b/modules/particles/include/SkCurve.h
index 076a1aa..044c0f4 100644
--- a/modules/particles/include/SkCurve.h
+++ b/modules/particles/include/SkCurve.h
@@ -9,6 +9,7 @@
#define SkCurve_DEFINED
#include "SkColor.h"
+#include "SkParticleData.h"
#include "SkScalar.h"
#include "SkTArray.h"
@@ -73,10 +74,12 @@
fSegments.push_back().setConstant(c);
}
- // Evaluate this curve at x, using random for curves that have ranged or bidirectional segments.
- SkScalar eval(SkScalar x, SkRandom& random) const;
+ SkScalar eval(const SkParticleUpdateParams& params, SkParticleState& ps) const;
void visitFields(SkFieldVisitor* v);
+ // Parameters that determine our x-value during evaluation
+ SkParticleValue fInput;
+
// It should always be true that (fXValues.count() + 1) == fSegments.count()
SkTArray<SkScalar, true> fXValues;
SkTArray<SkCurveSegment, true> fSegments;
@@ -96,7 +99,7 @@
}
}
- SkColor4f eval(SkScalar x, SkRandom& random) const;
+ SkColor4f eval(SkScalar x, SkScalar t) const;
void visitFields(SkFieldVisitor* v);
void setConstant(SkColor4f c) {
@@ -117,9 +120,10 @@
fSegments.push_back().setConstant(c);
}
- SkColor4f eval(SkScalar x, SkRandom& random) const;
+ SkColor4f eval(const SkParticleUpdateParams& params, SkParticleState& ps) const;
void visitFields(SkFieldVisitor* v);
+ SkParticleValue fInput;
SkTArray<SkScalar, true> fXValues;
SkTArray<SkColorCurveSegment, true> fSegments;
};
diff --git a/modules/particles/include/SkParticleAffector.h b/modules/particles/include/SkParticleAffector.h
index 0efc54b..634d555 100644
--- a/modules/particles/include/SkParticleAffector.h
+++ b/modules/particles/include/SkParticleAffector.h
@@ -10,24 +10,17 @@
#include "SkReflected.h"
+#include "SkParticleData.h"
#include "SkPoint.h"
struct SkColorCurve;
struct SkCurve;
-struct SkParticleState;
-struct SkParticleUpdateParams;
-
-enum SkParticleFrame {
- kWorld_ParticleFrame, // "Up" is { 0, -1 }
- kLocal_ParticleFrame, // "Up" is particle's heading
- kVelocity_ParticleFrame, // "Up" is particle's direction of travel
-};
class SkParticleAffector : public SkReflected {
public:
REFLECTED_ABSTRACT(SkParticleAffector, SkReflected)
- void apply(SkParticleUpdateParams& params, SkParticleState ps[], int count);
+ void apply(const SkParticleUpdateParams& params, SkParticleState ps[], int count);
void visitFields(SkFieldVisitor* v) override;
static void RegisterAffectorTypes();
@@ -53,7 +46,7 @@
static sk_sp<SkParticleAffector> MakeColor(const SkColorCurve& curve);
private:
- virtual void onApply(SkParticleUpdateParams& params, SkParticleState ps[], int count) = 0;
+ virtual void onApply(const SkParticleUpdateParams& params, SkParticleState ps[], int count) = 0;
bool fEnabled = true;
};
diff --git a/modules/particles/include/SkParticleData.h b/modules/particles/include/SkParticleData.h
index e0fa771..906f811 100644
--- a/modules/particles/include/SkParticleData.h
+++ b/modules/particles/include/SkParticleData.h
@@ -11,12 +11,25 @@
#include "SkColor.h"
#include "SkPoint.h"
#include "SkRandom.h"
+#include "SkReflected.h"
#include "SkRSXform.h"
/*
* Various structs used to communicate particle information among emitters, affectors, etc.
*/
+enum SkParticleFrame {
+ kWorld_ParticleFrame, // "Up" is { 0, -1 }
+ kLocal_ParticleFrame, // "Up" is particle's heading
+ kVelocity_ParticleFrame, // "Up" is particle's direction of travel
+};
+
+static constexpr SkFieldVisitor::EnumStringMapping gParticleFrameMapping[] = {
+ { kWorld_ParticleFrame, "World" },
+ { kLocal_ParticleFrame, "Local" },
+ { kVelocity_ParticleFrame, "Velocity" },
+};
+
struct SkParticlePose {
SkPoint fPosition;
SkVector fHeading;
@@ -44,10 +57,83 @@
SkColor4f fColor;
SkScalar fFrame; // Parameter to drawable for animated sprites, etc.
SkRandom fRandom;
+
+ SkVector getFrameHeading(SkParticleFrame frame) const {
+ switch (frame) {
+ case kLocal_ParticleFrame:
+ return fPose.fHeading;
+ case kVelocity_ParticleFrame: {
+ SkVector heading = fVelocity.fLinear;
+ if (!heading.normalize()) {
+ heading.set(0, -1);
+ }
+ return heading;
+ }
+ case kWorld_ParticleFrame:
+ default:
+ return SkVector{ 0, -1 };
+ }
+ }
};
struct SkParticleUpdateParams {
float fDeltaTime;
+ float fEffectAge;
+ int fAgeSource;
+};
+
+/**
+ * SkParticleValue selects a specific value to be used when evaluating a curve, position on a path,
+ * or any other affector that needs a scalar float input. An SkParticleValue starts with a source
+ * value taken from the state of the effect or particle. That can be adjusted using a scale and
+ * bias, and then reduced into the desired range (typically [0, 1]) via a chosen tile mode.
+ */
+struct SkParticleValue {
+ enum Source {
+ // Either the particle or effect age, depending on spawn or update
+ kAge_Source,
+
+ kRandom_Source,
+ kParticleAge_Source,
+ kEffectAge_Source,
+ kPositionX_Source,
+ kPositionY_Source,
+ kHeadingX_Source,
+ kHeadingY_Source,
+ kScale_Source,
+ kVelocityX_Source,
+ kVelocityY_Source,
+ kRotation_Source,
+ kColorR_Source,
+ kColorG_Source,
+ kColorB_Source,
+ kColorA_Source,
+ kSpriteFrame_Source,
+ };
+
+ enum TileMode {
+ kClamp_TileMode,
+ kRepeat_TileMode,
+ kMirror_TileMode,
+ };
+
+ void visitFields(SkFieldVisitor* v);
+ float eval(const SkParticleUpdateParams& params, SkParticleState& ps) const;
+
+ int fSource = kAge_Source;
+ int fFrame = kWorld_ParticleFrame;
+ int fTileMode = kRepeat_TileMode;
+
+ // We map fLeft -> 0 and fRight -> 1. This is easier to work with and reason about.
+ float fLeft = 0.0f;
+ float fRight = 1.0f;
+
+ // Cached from the above
+ float fScale = 1.0f;
+ float fBias = 0.0f;
+
+private:
+ float getSourceValue(const SkParticleUpdateParams& params, SkParticleState& ps) const;
};
#endif // SkParticleData_DEFINED
diff --git a/modules/particles/include/SkReflected.h b/modules/particles/include/SkReflected.h
index 0904a31..a7d787c 100644
--- a/modules/particles/include/SkReflected.h
+++ b/modules/particles/include/SkReflected.h
@@ -9,13 +9,13 @@
#define SkReflected_DEFINED
#include "SkColor.h"
-#include "SkCurve.h"
#include "SkRefCnt.h"
#include "SkString.h"
#include "SkTArray.h"
#include <string.h>
+struct SkCurve;
class SkFieldVisitor;
class SkRandom;
@@ -158,11 +158,7 @@
virtual void visit(const char*, int&, const EnumStringMapping*, int count) = 0;
// Specific virtual signature for SkCurve, to allow for heavily customized UI in SkGuiVisitor.
- virtual void visit(const char* name, SkCurve& c) {
- this->enterObject(name);
- c.visitFields(this);
- this->exitObject();
- }
+ virtual void visit(const char* name, SkCurve& c);
// Default visit function for structs with no special behavior. It is assumed that any such
// struct implements visitFields(SkFieldVisitor*) to recursively visit each of its fields.
diff --git a/modules/particles/src/SkCurve.cpp b/modules/particles/src/SkCurve.cpp
index 3dc7819..5dcfb60d 100644
--- a/modules/particles/src/SkCurve.cpp
+++ b/modules/particles/src/SkCurve.cpp
@@ -7,6 +7,7 @@
#include "SkCurve.h"
+#include "SkParticleData.h"
#include "SkRandom.h"
#include "SkReflected.h"
@@ -78,9 +79,11 @@
}
}
-SkScalar SkCurve::eval(SkScalar x, SkRandom& random) const {
+SkScalar SkCurve::eval(const SkParticleUpdateParams& params, SkParticleState& ps) const {
SkASSERT(fSegments.count() == fXValues.count() + 1);
+ float x = fInput.eval(params, ps);
+
int i = 0;
for (; i < fXValues.count(); ++i) {
if (x <= fXValues[i]) {
@@ -98,12 +101,13 @@
// Always pull t and negate here, so that the stable generator behaves consistently, even if
// our segments use an inconsistent feature-set.
- SkScalar t = random.nextF();
- bool negate = random.nextBool();
+ SkScalar t = ps.fRandom.nextF();
+ bool negate = ps.fRandom.nextBool();
return fSegments[i].eval(segmentX, t, negate);
}
void SkCurve::visitFields(SkFieldVisitor* v) {
+ v->visit("Input", fInput);
v->visit("XValues", fXValues);
v->visit("Segments", fSegments);
@@ -117,10 +121,10 @@
}
}
-SkColor4f SkColorCurveSegment::eval(SkScalar x, SkRandom& random) const {
+SkColor4f SkColorCurveSegment::eval(SkScalar x, SkScalar t) const {
SkColor4f result = eval_segment(fMin, x, fType);
if (fRanged) {
- result = result + (eval_segment(fMax, x, fType) - result) * random.nextF();
+ result = result + (eval_segment(fMax, x, fType) - result) * t;
}
return result;
}
@@ -148,9 +152,11 @@
}
}
-SkColor4f SkColorCurve::eval(SkScalar x, SkRandom& random) const {
+SkColor4f SkColorCurve::eval(const SkParticleUpdateParams& params, SkParticleState& ps) const {
SkASSERT(fSegments.count() == fXValues.count() + 1);
+ float x = fInput.eval(params, ps);
+
int i = 0;
for (; i < fXValues.count(); ++i) {
if (x <= fXValues[i]) {
@@ -165,10 +171,11 @@
segmentX = rangeMin;
}
SkASSERT(0.0f <= segmentX && segmentX <= 1.0f);
- return fSegments[i].eval(segmentX, random);
+ return fSegments[i].eval(segmentX, ps.fRandom.nextF());
}
void SkColorCurve::visitFields(SkFieldVisitor* v) {
+ v->visit("Input", fInput);
v->visit("XValues", fXValues);
v->visit("Segments", fSegments);
diff --git a/modules/particles/src/SkParticleAffector.cpp b/modules/particles/src/SkParticleAffector.cpp
index 9904ca2..655fa29 100644
--- a/modules/particles/src/SkParticleAffector.cpp
+++ b/modules/particles/src/SkParticleAffector.cpp
@@ -17,13 +17,8 @@
#include "sk_tool_utils.h"
-constexpr SkFieldVisitor::EnumStringMapping gParticleFrameMapping[] = {
- { kWorld_ParticleFrame, "World" },
- { kLocal_ParticleFrame, "Local" },
- { kVelocity_ParticleFrame, "Velocity" },
-};
-
-void SkParticleAffector::apply(SkParticleUpdateParams& params, SkParticleState ps[], int count) {
+void SkParticleAffector::apply(const SkParticleUpdateParams& params,
+ SkParticleState ps[], int count) {
if (fEnabled) {
this->onApply(params, ps, count);
}
@@ -33,23 +28,6 @@
v->visit("Enabled", fEnabled);
}
-static inline SkVector get_heading(const SkParticleState& ps, SkParticleFrame frame) {
- switch (frame) {
- case kLocal_ParticleFrame:
- return ps.fPose.fHeading;
- case kVelocity_ParticleFrame: {
- SkVector heading = ps.fVelocity.fLinear;
- if (!heading.normalize()) {
- heading.set(0, -1);
- }
- return heading;
- }
- case kWorld_ParticleFrame:
- default:
- return SkVector{ 0, -1 };
- }
-}
-
class SkLinearVelocityAffector : public SkParticleAffector {
public:
SkLinearVelocityAffector(const SkCurve& angle = 0.0f,
@@ -63,14 +41,14 @@
REFLECTED(SkLinearVelocityAffector, SkParticleAffector)
- void onApply(SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
+ void onApply(const SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
for (int i = 0; i < count; ++i) {
- float angle = fAngle.eval(ps[i].fAge, ps[i].fRandom);
+ float angle = fAngle.eval(params, ps[i]);
SkScalar c_local, s_local = SkScalarSinCos(SkDegreesToRadians(angle), &c_local);
- SkVector heading = get_heading(ps[i], static_cast<SkParticleFrame>(fFrame));
+ SkVector heading = ps[i].getFrameHeading(static_cast<SkParticleFrame>(fFrame));
SkScalar c = heading.fX * c_local - heading.fY * s_local;
SkScalar s = heading.fX * s_local + heading.fY * c_local;
- float strength = fStrength.eval(ps[i].fAge, ps[i].fRandom);
+ float strength = fStrength.eval(params, ps[i]);
SkVector force = { c * strength, s * strength };
if (fForce) {
ps[i].fVelocity.fLinear += force * params.fDeltaTime;
@@ -103,9 +81,9 @@
REFLECTED(SkAngularVelocityAffector, SkParticleAffector)
- void onApply(SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
+ void onApply(const SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
for (int i = 0; i < count; ++i) {
- float strength = fStrength.eval(ps[i].fAge, ps[i].fRandom);
+ float strength = fStrength.eval(params, ps[i]);
if (fForce) {
ps[i].fVelocity.fAngular += strength * params.fDeltaTime;
} else {
@@ -133,7 +111,7 @@
REFLECTED(SkPointForceAffector, SkParticleAffector)
- void onApply(SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
+ void onApply(const SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
for (int i = 0; i < count; ++i) {
SkVector toPoint = fPoint - ps[i].fPose.fPosition;
SkScalar lenSquare = toPoint.dot(toPoint);
@@ -165,11 +143,11 @@
REFLECTED(SkOrientationAffector, SkParticleAffector)
- void onApply(SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
+ void onApply(const SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
for (int i = 0; i < count; ++i) {
- float angle = fAngle.eval(ps[i].fAge, ps[i].fRandom);
+ float angle = fAngle.eval(params, ps[i]);
SkScalar c_local, s_local = SkScalarSinCos(SkDegreesToRadians(angle), &c_local);
- SkVector heading = get_heading(ps[i], static_cast<SkParticleFrame>(fFrame));
+ SkVector heading = ps[i].getFrameHeading(static_cast<SkParticleFrame>(fFrame));
ps[i].fPose.fHeading.set(heading.fX * c_local - heading.fY * s_local,
heading.fX * s_local + heading.fY * c_local);
}
@@ -197,7 +175,7 @@
REFLECTED(SkPositionInCircleAffector, SkParticleAffector)
- void onApply(SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
+ void onApply(const SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
for (int i = 0; i < count; ++i) {
SkVector v;
do {
@@ -205,9 +183,8 @@
v.fY = ps[i].fRandom.nextSScalar1();
} while (v.dot(v) > 1);
- SkPoint center = { fX.eval(ps[i].fAge, ps[i].fRandom),
- fY.eval(ps[i].fAge, ps[i].fRandom) };
- SkScalar radius = fRadius.eval(ps[i].fAge, ps[i].fRandom);
+ SkPoint center = { fX.eval(params, ps[i]), fY.eval(params, ps[i]) };
+ SkScalar radius = fRadius.eval(params, ps[i]);
ps[i].fPose.fPosition = center + (v * radius);
if (fSetHeading) {
if (!v.normalize()) {
@@ -235,22 +212,23 @@
class SkPositionOnPathAffector : public SkParticleAffector {
public:
- SkPositionOnPathAffector(const char* path = "", bool setHeading = true, bool random = true)
+ SkPositionOnPathAffector(const char* path = "", bool setHeading = true,
+ SkParticleValue input = SkParticleValue())
: fPath(path)
- , fSetHeading(setHeading)
- , fRandom(random) {
+ , fInput(input)
+ , fSetHeading(setHeading) {
this->rebuild();
}
REFLECTED(SkPositionOnPathAffector, SkParticleAffector)
- void onApply(SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
+ void onApply(const SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
if (fContours.empty()) {
return;
}
for (int i = 0; i < count; ++i) {
- float t = fRandom ? ps[i].fRandom.nextF() : ps[i].fAge;
+ float t = fInput.eval(params, ps[i]);
SkScalar len = fTotalLength * t;
int idx = 0;
while (idx < fContours.count() && len > fContours[idx]->length()) {
@@ -271,8 +249,8 @@
SkString oldPath = fPath;
SkParticleAffector::visitFields(v);
+ v->visit("Input", fInput);
v->visit("SetHeading", fSetHeading);
- v->visit("Random", fRandom);
v->visit("Path", fPath);
if (fPath != oldPath) {
@@ -281,9 +259,9 @@
}
private:
- SkString fPath;
- bool fSetHeading;
- bool fRandom;
+ SkString fPath;
+ SkParticleValue fInput;
+ bool fSetHeading;
void rebuild() {
SkPath path;
@@ -309,24 +287,24 @@
class SkPositionOnTextAffector : public SkParticleAffector {
public:
SkPositionOnTextAffector(const char* text = "", SkScalar fontSize = 96, bool setHeading = true,
- bool random = true)
+ SkParticleValue input = SkParticleValue())
: fText(text)
, fFontSize(fontSize)
- , fSetHeading(setHeading)
- , fRandom(random) {
+ , fInput(input)
+ , fSetHeading(setHeading) {
this->rebuild();
}
REFLECTED(SkPositionOnTextAffector, SkParticleAffector)
- void onApply(SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
+ void onApply(const SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
if (fContours.empty()) {
return;
}
// TODO: Refactor to share code with PositionOnPathAffector
for (int i = 0; i < count; ++i) {
- float t = fRandom ? ps[i].fRandom.nextF() : ps[i].fAge;
+ float t = fInput.eval(params, ps[i]);
SkScalar len = fTotalLength * t;
int idx = 0;
while (idx < fContours.count() && len > fContours[idx]->length()) {
@@ -348,8 +326,8 @@
SkScalar oldSize = fFontSize;
SkParticleAffector::visitFields(v);
+ v->visit("Input", fInput);
v->visit("SetHeading", fSetHeading);
- v->visit("Random", fRandom);
v->visit("Text", fText);
v->visit("FontSize", fFontSize);
@@ -359,10 +337,10 @@
}
private:
- SkString fText;
- SkScalar fFontSize;
- bool fSetHeading;
- bool fRandom;
+ SkString fText;
+ SkScalar fFontSize;
+ SkParticleValue fInput;
+ bool fSetHeading;
void rebuild() {
fTotalLength = 0;
@@ -394,9 +372,9 @@
REFLECTED(SkSizeAffector, SkParticleAffector)
- void onApply(SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
+ void onApply(const SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
for (int i = 0; i < count; ++i) {
- ps[i].fPose.fScale = fCurve.eval(ps[i].fAge, ps[i].fRandom);
+ ps[i].fPose.fScale = fCurve.eval(params, ps[i]);
}
}
@@ -415,9 +393,9 @@
REFLECTED(SkFrameAffector, SkParticleAffector)
- void onApply(SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
+ void onApply(const SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
for (int i = 0; i < count; ++i) {
- ps[i].fFrame = fCurve.eval(ps[i].fAge, ps[i].fRandom);
+ ps[i].fFrame = fCurve.eval(params, ps[i]);
}
}
@@ -437,9 +415,9 @@
REFLECTED(SkColorAffector, SkParticleAffector)
- void onApply(SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
+ void onApply(const SkParticleUpdateParams& params, SkParticleState ps[], int count) override {
for (int i = 0; i < count; ++i) {
- ps[i].fColor = fCurve.eval(ps[i].fAge, ps[i].fRandom);
+ ps[i].fColor = fCurve.eval(params, ps[i]);
}
}
diff --git a/modules/particles/src/SkParticleEffect.cpp b/modules/particles/src/SkParticleEffect.cpp
index d1f7b64..2b6a88e 100644
--- a/modules/particles/src/SkParticleEffect.cpp
+++ b/modules/particles/src/SkParticleEffect.cpp
@@ -64,8 +64,15 @@
this->setCapacity(fParams->fMaxCount);
}
+ float effectAge = static_cast<float>((now - fSpawnTime) / fParams->fEffectDuration);
+ effectAge = fLooping ? fmodf(effectAge, 1.0f) : SkTPin(effectAge, 0.0f, 1.0f);
+
SkParticleUpdateParams updateParams;
updateParams.fDeltaTime = deltaTime;
+ updateParams.fEffectAge = effectAge;
+
+ // During spawn, values that refer to kAge_Source get the *effect* age
+ updateParams.fAgeSource = SkParticleValue::kEffectAge_Source;
// Advance age for existing particles, and remove any that have reached their end of life
for (int i = 0; i < fCount; ++i) {
@@ -85,18 +92,12 @@
fSpawnRemainder = desired - numToSpawn;
numToSpawn = SkTPin(numToSpawn, 0, fParams->fMaxCount - fCount);
if (numToSpawn) {
- // This isn't "particle" t, it's effect t.
- float t = static_cast<float>((now - fSpawnTime) / fParams->fEffectDuration);
- t = fLooping ? fmodf(t, 1.0f) : SkTPin(t, 0.0f, 1.0f);
+ const int spawnBase = fCount;
for (int i = 0; i < numToSpawn; ++i) {
// Mutate our SkRandom so each particle definitely gets a different stable generator
fRandom.nextU();
-
- // Temporarily set our age to the *effect* age, so spawn affectors are driven by that
- fParticles[fCount].fAge = t;
- fParticles[fCount].fInvLifetime =
- sk_ieee_float_divide(1.0f, fParams->fLifetime.eval(t, fRandom));
+ fParticles[fCount].fAge = 0.0f;
fParticles[fCount].fPose.fPosition = { 0.0f, 0.0f };
fParticles[fCount].fPose.fHeading = { 0.0f, -1.0f };
fParticles[fCount].fPose.fScale = 1.0f;
@@ -104,19 +105,21 @@
fParticles[fCount].fVelocity.fAngular = 0.0f;
fParticles[fCount].fColor = { 1.0f, 1.0f, 1.0f, 1.0f };
fParticles[fCount].fFrame = 0.0f;
-
fParticles[fCount].fRandom = fStableRandoms[fCount] = fRandom;
fCount++;
}
- // Apply spawn affectors, then reset our age to 0 (the *particle* age)
+ // Apply spawn affectors
for (auto affector : fParams->fSpawnAffectors) {
if (affector) {
- affector->apply(updateParams, fParticles + (fCount - numToSpawn), numToSpawn);
+ affector->apply(updateParams, fParticles + spawnBase, numToSpawn);
}
}
- for (int i = fCount - numToSpawn; i < fCount; ++i) {
- fParticles[i].fAge = 0.0f;
+
+ // Now compute particle lifetimes (so the curve can refer to spawn-computed source values)
+ for (int i = spawnBase; i < fCount; ++i) {
+ fParticles[i].fInvLifetime =
+ sk_ieee_float_divide(1.0f, fParams->fLifetime.eval(updateParams, fParticles[i]));
}
}
@@ -125,6 +128,9 @@
fParticles[i].fRandom = fStableRandoms[i];
}
+ // During update, values that refer to kAge_Source get the *particle* age
+ updateParams.fAgeSource = SkParticleValue::kParticleAge_Source;
+
// Apply update rules
for (auto affector : fParams->fUpdateAffectors) {
if (affector) {
@@ -163,3 +169,116 @@
fCapacity = capacity;
fCount = SkTMin(fCount, fCapacity);
}
+
+constexpr SkFieldVisitor::EnumStringMapping gValueSourceMapping[] = {
+ { SkParticleValue::kAge_Source, "Age" },
+ { SkParticleValue::kRandom_Source, "Random" },
+ { SkParticleValue::kParticleAge_Source, "ParticleAge" },
+ { SkParticleValue::kEffectAge_Source, "EffectAge" },
+ { SkParticleValue::kPositionX_Source, "PositionX" },
+ { SkParticleValue::kPositionY_Source, "PositionY" },
+ { SkParticleValue::kHeadingX_Source, "HeadingX" },
+ { SkParticleValue::kHeadingY_Source, "HeadingY" },
+ { SkParticleValue::kScale_Source, "Scale" },
+ { SkParticleValue::kVelocityX_Source, "VelocityX" },
+ { SkParticleValue::kVelocityY_Source, "VelocityY" },
+ { SkParticleValue::kRotation_Source, "Rotation" },
+ { SkParticleValue::kColorR_Source, "ColorR" },
+ { SkParticleValue::kColorG_Source, "ColorG" },
+ { SkParticleValue::kColorB_Source, "ColorB" },
+ { SkParticleValue::kColorA_Source, "ColorA" },
+ { SkParticleValue::kSpriteFrame_Source, "SpriteFrame" },
+};
+
+constexpr SkFieldVisitor::EnumStringMapping gValueTileModeMapping[] = {
+ { SkParticleValue::kClamp_TileMode, "Clamp" },
+ { SkParticleValue::kRepeat_TileMode, "Repeat" },
+ { SkParticleValue::kMirror_TileMode, "Mirror" },
+};
+
+static bool source_needs_frame(int source) {
+ switch (source) {
+ case SkParticleValue::kHeadingX_Source:
+ case SkParticleValue::kHeadingY_Source:
+ case SkParticleValue::kVelocityX_Source:
+ case SkParticleValue::kVelocityY_Source:
+ return true;
+ default:
+ return false;
+ }
+}
+
+void SkParticleValue::visitFields(SkFieldVisitor* v) {
+ v->visit("Source", fSource, gValueSourceMapping, SK_ARRAY_COUNT(gValueSourceMapping));
+ if (source_needs_frame(fSource)) {
+ v->visit("Frame", fFrame, gParticleFrameMapping, SK_ARRAY_COUNT(gParticleFrameMapping));
+ }
+ v->visit("TileMode", fTileMode, gValueTileModeMapping, SK_ARRAY_COUNT(gValueTileModeMapping));
+ v->visit("Left", fLeft);
+ v->visit("Right", fRight);
+
+ // Re-compute cached evaluation parameters
+ fScale = sk_float_isfinite(1.0f / (fRight - fLeft)) ? 1.0f / (fRight - fLeft) : 0;
+ fBias = -fLeft * fScale;
+}
+
+float SkParticleValue::getSourceValue(const SkParticleUpdateParams& params,
+ SkParticleState& ps) const {
+ switch ((kAge_Source == fSource) ? params.fAgeSource : fSource) {
+ // Do all the simple (non-frame-dependent) sources first:
+ case kRandom_Source: return ps.fRandom.nextF();
+ case kParticleAge_Source: return ps.fAge;
+ case kEffectAge_Source: return params.fEffectAge;
+
+ case kPositionX_Source: return ps.fPose.fPosition.fX;
+ case kPositionY_Source: return ps.fPose.fPosition.fY;
+ case kScale_Source: return ps.fPose.fScale;
+ case kRotation_Source: return ps.fVelocity.fAngular;
+
+ case kColorR_Source: return ps.fColor.fR;
+ case kColorG_Source: return ps.fColor.fG;
+ case kColorB_Source: return ps.fColor.fB;
+ case kColorA_Source: return ps.fColor.fA;
+ case kSpriteFrame_Source: return ps.fFrame;
+ }
+
+ SkASSERT(source_needs_frame(fSource));
+ SkVector frameUp = ps.getFrameHeading(static_cast<SkParticleFrame>(fFrame));
+ SkVector frameRight = { -frameUp.fY, frameUp.fX };
+
+ switch (fSource) {
+ case kHeadingX_Source: return ps.fPose.fHeading.dot(frameRight);
+ case kHeadingY_Source: return ps.fPose.fHeading.dot(frameUp);
+ case kVelocityX_Source: return ps.fVelocity.fLinear.dot(frameRight);
+ case kVelocityY_Source: return ps.fVelocity.fLinear.dot(frameUp);
+ }
+
+ SkDEBUGFAIL("Unreachable");
+ return 0.0f;
+}
+
+float SkParticleValue::eval(const SkParticleUpdateParams& params, SkParticleState& ps) const {
+ float v = this->getSourceValue(params, ps);
+ v = (v * fScale) + fBias;
+
+ switch (fTileMode) {
+ case kClamp_TileMode:
+ v = SkTPin(v, 0.0f, 1.0f);
+ break;
+ case kRepeat_TileMode:
+ v = sk_float_mod(v, 1.0f);
+ if (v < 0) {
+ v += 1.0f;
+ }
+ break;
+ case kMirror_TileMode:
+ v = sk_float_mod(v, 2.0f);
+ if (v < 0) {
+ v += 2.0f;
+ }
+ v = 1.0f - sk_float_abs(v - 1.0f);
+ break;
+ }
+
+ return v;
+}
diff --git a/modules/particles/src/SkReflected.cpp b/modules/particles/src/SkReflected.cpp
index 48458cc..4b781d9 100644
--- a/modules/particles/src/SkReflected.cpp
+++ b/modules/particles/src/SkReflected.cpp
@@ -7,6 +7,8 @@
#include "SkReflected.h"
+#include "SkCurve.h"
+
SkSTArray<16, const SkReflected::Type*, true> SkReflected::gTypes;
void SkReflected::VisitTypes(std::function<void(const Type*)> visitor, const Type* baseType) {
@@ -16,3 +18,9 @@
}
}
}
+
+void SkFieldVisitor::visit(const char* name, SkCurve& c) {
+ this->enterObject(name);
+ c.visitFields(this);
+ this->exitObject();
+}
diff --git a/resources/particles/default.json b/resources/particles/default.json
index 8f220f3..6c5f5cc 100644
--- a/resources/particles/default.json
+++ b/resources/particles/default.json
@@ -3,6 +3,12 @@
"Duration": 1,
"Rate": 1000,
"Life": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -25,6 +31,12 @@
"Force": false,
"Frame": "World",
"Angle": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -37,6 +49,12 @@
]
},
"Strength": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -52,6 +70,12 @@
{
"Type": "SkPositionOnTextAffector",
"Enabled": true,
+ "Input": {
+ "Source": "Random",
+ "TileMode": "Clamp",
+ "Left": 0,
+ "Right": 1
+ },
"SetHeading": true,
"Text": "SKIA",
"FontSize": 96
@@ -62,6 +86,12 @@
"Type": "SkColorAffector",
"Enabled": true,
"Curve": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
diff --git a/resources/particles/explosion.json b/resources/particles/explosion.json
index 238f352..23835a7 100644
--- a/resources/particles/explosion.json
+++ b/resources/particles/explosion.json
@@ -3,6 +3,12 @@
"Duration": 1,
"Rate": 8,
"Life": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -26,6 +32,12 @@
"Enabled": true,
"SetHeading": true,
"X": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -37,6 +49,12 @@
]
},
"Y": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -48,6 +66,12 @@
]
},
"Radius": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -72,6 +96,12 @@
"Type": "SkFrameAffector",
"Enabled": true,
"Curve": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
diff --git a/resources/particles/penguin_cannon.json b/resources/particles/penguin_cannon.json
index 227a1af..3891bef 100644
--- a/resources/particles/penguin_cannon.json
+++ b/resources/particles/penguin_cannon.json
@@ -3,6 +3,12 @@
"Duration": 1,
"Rate": 0.5,
"Life": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -26,6 +32,12 @@
"Force": false,
"Frame": "World",
"Angle": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -38,6 +50,12 @@
]
},
"Strength": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -58,6 +76,12 @@
"Force": true,
"Frame": "World",
"Angle": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -69,6 +93,12 @@
]
},
"Strength": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -85,6 +115,12 @@
"Enabled": true,
"Frame": "Velocity",
"Angle": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
diff --git a/resources/particles/snowfall.json b/resources/particles/snowfall.json
index 2c796c8..1059601 100644
--- a/resources/particles/snowfall.json
+++ b/resources/particles/snowfall.json
@@ -3,6 +3,12 @@
"Duration": 1,
"Rate": 30,
"Life": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -24,6 +30,12 @@
"Force": false,
"Frame": "World",
"Angle": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -36,6 +48,12 @@
]
},
"Strength": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -51,6 +69,12 @@
{
"Type": "SkPositionOnPathAffector",
"Enabled": true,
+ "Input": {
+ "Source": "Random",
+ "TileMode": "Clamp",
+ "Left": 0,
+ "Right": 1
+ },
"SetHeading": false,
"Path": "h500"
}
@@ -60,6 +84,12 @@
"Type": "SkSizeAffector",
"Enabled": true,
"Curve": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
diff --git a/resources/particles/spiral.json b/resources/particles/spiral.json
index d52326d..9fda70d 100644
--- a/resources/particles/spiral.json
+++ b/resources/particles/spiral.json
@@ -3,6 +3,12 @@
"Duration": 4,
"Rate": 120,
"Life": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -25,6 +31,12 @@
"Force": false,
"Frame": "World",
"Angle": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -37,6 +49,12 @@
]
},
"Strength": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -55,6 +73,12 @@
"Type": "SkSizeAffector",
"Enabled": true,
"Curve": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -71,6 +95,12 @@
"Type": "SkColorAffector",
"Enabled": true,
"Curve": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
diff --git a/resources/particles/swirl.json b/resources/particles/swirl.json
index 23dc2a7..231a92d 100644
--- a/resources/particles/swirl.json
+++ b/resources/particles/swirl.json
@@ -3,6 +3,12 @@
"Duration": 1,
"Rate": 400,
"Life": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -22,6 +28,12 @@
{
"Type": "SkPositionOnPathAffector",
"Enabled": true,
+ "Input": {
+ "Source": "Random",
+ "TileMode": "Clamp",
+ "Left": 0,
+ "Right": 1
+ },
"SetHeading": true,
"Path": "h50"
},
@@ -31,6 +43,12 @@
"Force": false,
"Frame": "World",
"Angle": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -43,6 +61,12 @@
]
},
"Strength": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -63,6 +87,12 @@
"Force": true,
"Frame": "World",
"Angle": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -74,6 +104,12 @@
]
},
"Strength": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -92,6 +128,12 @@
"Type": "SkSizeAffector",
"Enabled": true,
"Curve": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -108,6 +150,12 @@
"Type": "SkColorAffector",
"Enabled": true,
"Curve": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
diff --git a/resources/particles/warp.json b/resources/particles/warp.json
index 96ede19..cc079fd 100644
--- a/resources/particles/warp.json
+++ b/resources/particles/warp.json
@@ -3,6 +3,12 @@
"Duration": 1,
"Rate": 90,
"Life": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -23,6 +29,12 @@
"Enabled": true,
"SetHeading": true,
"X": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -34,6 +46,12 @@
]
},
"Y": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -45,6 +63,12 @@
]
},
"Radius": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
@@ -69,6 +93,12 @@
"Type": "SkSizeAffector",
"Enabled": true,
"Curve": {
+ "Input": {
+ "Source": "Age",
+ "TileMode": "Repeat",
+ "Left": 0,
+ "Right": 1
+ },
"XValues": [],
"Segments": [
{
diff --git a/tools/viewer/ParticlesSlide.cpp b/tools/viewer/ParticlesSlide.cpp
index 343d16f..a14b647 100644
--- a/tools/viewer/ParticlesSlide.cpp
+++ b/tools/viewer/ParticlesSlide.cpp
@@ -215,7 +215,7 @@
if (fTimer && ImGui::Button("Play")) {
fEffect->start(*fTimer, looped);
}
- static char filename[64] = "resources/particles/default.json";
+ static char filename[64] = "particles/default.json";
ImGui::InputText("Filename", filename, sizeof(filename));
if (ImGui::Button("Load")) {
if (auto newParams = LoadEffectParams(filename)) {
@@ -225,7 +225,8 @@
ImGui::SameLine();
if (ImGui::Button("Save")) {
- SkFILEWStream fileStream(filename);
+ SkString fullPath = GetResourcePath(filename);
+ SkFILEWStream fileStream(fullPath.c_str());
if (fileStream.isValid()) {
SkJSONWriter writer(&fileStream, SkJSONWriter::Mode::kPretty);
SkToJsonVisitor toJson(writer);