lottie/slot: revise gradient fill support

Revise gradient fill data parsing by adding support
for the color stop count (p) parameter in slot data.

issue: https://github.com/thorvg/thorvg/issues/2795

examples/LottieExtension.cpp

@@ -96,7 +96,7 @@ struct UserExample : tvgexam::Example
             auto picture = slotAnimation->picture();
             if (!tvgexam::verify(picture->load(EXAMPLE_DIR"/lottie/extensions/slotsample.json"))) return false;
 
-            const char* slotJson = R"({"gradient_fill":{"p":{"a":0,"k":[0,0.1,0.1,0.2,1,1,0.1,0.2,0.1,1]}}})";
+            const char* slotJson = R"({"gradient_fill":{"p":{"p":2,"k":{"k":[0,0.1,0.1,0.2,1,1,0.1,0.2,0,0,1,1]}}}})";
             if (!tvgexam::verify(slotAnimation->override(slotJson))) return false;
 
             sizing(picture, 0);

examples/resources/lottie/extensions/slotsample.json

@@ -1 +1 @@
-{"v":"4.8.0","meta":{"g":"LottieFiles AE 3.0.2","a":"","k":"","d":"","tc":""},"fr":60,"ip":0,"op":121,"w":550,"h":550,"nm":"C","assets":[],"layers":[{"ind":1,"ty":4,"nm":"S","sr":1,"ks":{"o":{"a":0,"k":100},"r":{"a":1,"k":[{"i":{"x":[0.833],"y":[0.833]},"o":{"x":[0.167],"y":[0.167]},"t":0,"s":[0]},{"t":120,"s":[360]}]},"p":{"a":0,"k":[275,275,0]},"a":{"a":0,"k":[-7.886,88.719,0]},"s":{"a":0,"k":[100,100,100]}},"ao":0,"shapes":[{"ty":"gr","it":[{"ty":"rc","d":1,"s":{"a":0,"k":[282.019,134.888]},"p":{"a":0,"k":[0,0]},"r":{"a":0,"k":0},"nm":"R"},{"ty":"st","c":{"a":0,"k":[0.991,0,1,1]},"o":{"a":0,"k":100},"w":{"a":0,"k":3},"lc":1,"lj":1,"ml":4,"nm":"S"},{"ty":"gf","o":{"a":0,"k":100},"r":1,"g":{"p":9,"k":{"a":0,"k":[0,0.514,0.373,0.984,0.141,0.478,0.412,0.984,0.283,0.443,0.451,0.984,0.379,0.408,0.49,0.984,0.475,0.373,0.529,0.984,0.606,0.278,0.647,0.925,0.737,0.184,0.765,0.867,0.868,0.092,0.882,0.808,1,0,1,0.749],"sid":"gradient_fill"}},"s":{"a":0,"k":[-159.51,23.531]},"e":{"a":0,"k":[183.084,8.059]},"t":1,"nm":"G"},{"ty":"tr","p":{"a":0,"k":[-7.886,88.719]},"a":{"a":0,"k":[0,0]},"s":{"a":0,"k":[100,100]},"r":{"a":0,"k":0},"o":{"a":0,"k":100},"sk":{"a":0,"k":0},"sa":{"a":0,"k":0},"nm":"T"}],"nm":"R"}],"ip":0,"op":300,"st":0}],"slots":{"gradient_fill":{"p":{"a":0,"k":[0,0.1,0.1,0.2,1,1,0.1,0.2,0.1,1]}}},"markers":[]}
+{"v":"4.8.0","meta":{"g":"LottieFiles AE 3.0.2","a":"","k":"","d":"","tc":""},"fr":60,"ip":0,"op":121,"w":550,"h":550,"nm":"C","assets":[],"layers":[{"ind":1,"ty":4,"nm":"S","sr":1,"ks":{"o":{"a":0,"k":100},"r":{"a":1,"k":[{"i":{"x":[0.833],"y":[0.833]},"o":{"x":[0.167],"y":[0.167]},"t":0,"s":[0]},{"t":120,"s":[360]}]},"p":{"a":0,"k":[275,275,0]},"a":{"a":0,"k":[-7.886,88.719,0]},"s":{"a":0,"k":[100,100,100]}},"ao":0,"shapes":[{"ty":"gr","it":[{"ty":"rc","d":1,"s":{"a":0,"k":[282.019,134.888]},"p":{"a":0,"k":[0,0]},"r":{"a":0,"k":0},"nm":"R"},{"ty":"st","c":{"a":0,"k":[0.991,0,1,1]},"o":{"a":0,"k":100},"w":{"a":0,"k":3},"lc":1,"lj":1,"ml":4,"nm":"S"},{"ty":"gf","o":{"a":0,"k":100},"r":1,"g":{"p":9,"k":{"a":0,"k":[0,0.514,0.373,0.984,0.141,0.478,0.412,0.984,0.283,0.443,0.451,0.984,0.379,0.408,0.49,0.984,0.475,0.373,0.529,0.984,0.606,0.278,0.647,0.925,0.737,0.184,0.765,0.867,0.868,0.092,0.882,0.808,1,0,1,0.749]},"sid":"gradient_fill"},"s":{"a":0,"k":[-159.51,23.531]},"e":{"a":0,"k":[183.084,8.059]},"t":1,"nm":"G"},{"ty":"tr","p":{"a":0,"k":[-7.886,88.719]},"a":{"a":0,"k":[0,0]},"s":{"a":0,"k":[100,100]},"r":{"a":0,"k":0},"o":{"a":0,"k":100},"sk":{"a":0,"k":0},"sa":{"a":0,"k":0},"nm":"T"}],"nm":"R"}],"ip":0,"op":300,"st":0}],"slots":{"gradient_fill":{"p":{"a":0,"k":[0,0.1,0.1,0.2,1,1,0.1,0.2,0.1,1]}}},"markers":[]}

src/loaders/lottie/tvgLottieParser.cpp

@@ -485,26 +485,31 @@ void LottieParser::parsePropertyInternal(T& prop)
 }
 
 
+template<LottieProperty::Type type>
+void LottieParser::registerSlot(LottieObject* obj)
+{
+    auto sid = getStringCopy();
+
+    //append object if the slot already exists.
+    for (auto slot = comp->slots.begin(); slot < comp->slots.end(); ++slot) {
+        if (strcmp((*slot)->sid, sid)) continue;
+        (*slot)->pairs.push({obj});
+        return;
+    }
+    comp->slots.push(new LottieSlot(sid, obj, type));
+}
+
+
 template<LottieProperty::Type type, typename T>
 void LottieParser::parseProperty(T& prop, LottieObject* obj)
 {
     enterObject();
     while (auto key = nextObjectKey()) {
         if (KEY_AS("k")) parsePropertyInternal(prop);
-        else if (obj && KEY_AS("sid")) {
+        else if (obj && KEY_AS("sid")) registerSlot<type>(obj);
-            auto sid = getStringCopy();
+        else if (KEY_AS("x")) prop.exp = _expression(getStringCopy(), comp, context.layer, context.parent, &prop);
-            //append object if the slot already exists.
+        else if (KEY_AS("ix")) prop.ix = getInt();
-            for (auto slot = comp->slots.begin(); slot < comp->slots.end(); ++slot) {
+        else skip(key);
-                if (strcmp((*slot)->sid, sid)) continue;
-                (*slot)->pairs.push({obj});
-                break;
-            }
-            comp->slots.push(new LottieSlot(sid, obj, type));
-        } else if (KEY_AS("x")) {
-            prop.exp = _expression(getStringCopy(), comp, context.layer, context.parent, &prop);
-        } else if (KEY_AS("ix")) {
-            prop.ix = getInt();
-        } else skip(key);
     }
     prop.type = type;
 }
@@ -750,19 +755,23 @@ LottieRoundedCorner* LottieParser::parseRoundedCorner()
 }
 
 
-void LottieParser::parseGradient(LottieGradient* gradient, const char* key)
+void LottieParser::parseColorStop(LottieGradient* gradient)
 {
-    if (KEY_AS("t")) gradient->id = getInt();
-    else if (KEY_AS("o")) parseProperty<LottieProperty::Type::Opacity>(gradient->opacity, gradient);
-    else if (KEY_AS("g"))
-    {
     enterObject();
     while (auto key = nextObjectKey()) {
         if (KEY_AS("p")) gradient->colorStops.count = getInt();
         else if (KEY_AS("k")) parseProperty<LottieProperty::Type::ColorStop>(gradient->colorStops, gradient);
+        else if (KEY_AS("sid")) registerSlot<LottieProperty::Type::ColorStop>(gradient);
         else skip(key);
     }
-    }
+}
+
+
+void LottieParser::parseGradient(LottieGradient* gradient, const char* key)
+{
+    if (KEY_AS("t")) gradient->id = getInt();
+    else if (KEY_AS("o")) parseProperty<LottieProperty::Type::Opacity>(gradient->opacity, gradient);
+    else if (KEY_AS("g")) parseColorStop(gradient);
     else if (KEY_AS("s")) parseProperty<LottieProperty::Type::Point>(gradient->start, gradient);
     else if (KEY_AS("e")) parseProperty<LottieProperty::Type::Point>(gradient->end, gradient);
     else if (KEY_AS("h")) parseProperty<LottieProperty::Type::Float>(gradient->height, gradient);
@@ -1438,7 +1447,10 @@ bool LottieParser::apply(LottieSlot* slot)
         case LottieProperty::Type::ColorStop: {
             obj = new LottieGradient;
             context.parent = obj;
-            parseSlotProperty<LottieProperty::Type::ColorStop>(static_cast<LottieGradient*>(obj)->colorStops);
+            while (auto key = nextObjectKey()) {
+                if (KEY_AS("p")) parseColorStop(static_cast<LottieGradient*>(obj));
+                else skip(key);
+            }
             break;
         }
         case LottieProperty::Type::Color: {

src/loaders/lottie/tvgLottieParser.h

@@ -38,6 +38,7 @@ public:
     bool parse();
     bool apply(LottieSlot* slot);
     const char* sid(bool first = false);
+    template<LottieProperty::Type type = LottieProperty::Type::Invalid> void registerSlot(LottieObject* obj);
 
     LottieComposition* comp = nullptr;
     const char* dirName = nullptr;       //base resource directory
@@ -107,6 +108,7 @@ private:
     void parseTimeRemap(LottieLayer* layer);
     void parseStrokeDash(LottieStroke* stroke);
     void parseGradient(LottieGradient* gradient, const char* key);
+    void parseColorStop(LottieGradient* gradient);
     void parseTextRange(LottieText* text);
     void parseAssets();
     void parseFonts();

test/capi/capiLottie.cpp

@@ -41,7 +41,7 @@ TEST_CASE("Lottie Slot", "[capiLottie]")
     REQUIRE(tvg_paint_get_type(picture, &type) == TVG_RESULT_SUCCESS);
     REQUIRE(type == TVG_TYPE_PICTURE);
 
-    const char* slotJson = R"({"gradient_fill":{"p":{"a":0,"k":[0,0.1,0.1,0.2,1,1,0.1,0.2,0.1,1]}}})";
+    const char* slotJson = R"({"gradient_fill":{"p":{"p":2,"k":{"a":0,"k":[0,0.1,0.1,0.2,1,1,0.1,0.2,0.1,1]}}}})";
 
     //Slot override before loaded
     REQUIRE(tvg_lottie_animation_override(animation, slotJson) == TVG_RESULT_INSUFFICIENT_CONDITION);

test/resources/lottieslot.json

@@ -1 +1 @@
-{"v":"4.8.0","meta":{"g":"LottieFiles AE 3.0.2","a":"","k":"","d":"","tc":""},"fr":60,"ip":0,"op":121,"w":550,"h":550,"nm":"C","assets":[],"layers":[{"ind":1,"ty":4,"nm":"S","sr":1,"ks":{"o":{"a":0,"k":100},"r":{"a":1,"k":[{"i":{"x":[0.833],"y":[0.833]},"o":{"x":[0.167],"y":[0.167]},"t":0,"s":[0]},{"t":120,"s":[360]}]},"p":{"a":0,"k":[275,275,0]},"a":{"a":0,"k":[-7.886,88.719,0]},"s":{"a":0,"k":[100,100,100]}},"ao":0,"shapes":[{"ty":"gr","it":[{"ty":"rc","d":1,"s":{"a":0,"k":[282.019,134.888]},"p":{"a":0,"k":[0,0]},"r":{"a":0,"k":0},"nm":"R"},{"ty":"st","c":{"a":0,"k":[0.991,0,1,1]},"o":{"a":0,"k":100},"w":{"a":0,"k":3},"lc":1,"lj":1,"ml":4,"nm":"S"},{"ty":"gf","o":{"a":0,"k":100},"r":1,"g":{"p":9,"k":{"a":0,"k":[0,0.514,0.373,0.984,0.141,0.478,0.412,0.984,0.283,0.443,0.451,0.984,0.379,0.408,0.49,0.984,0.475,0.373,0.529,0.984,0.606,0.278,0.647,0.925,0.737,0.184,0.765,0.867,0.868,0.092,0.882,0.808,1,0,1,0.749],"sid":"gradient_fill"}},"s":{"a":0,"k":[-159.51,23.531]},"e":{"a":0,"k":[183.084,8.059]},"t":1,"nm":"G"},{"ty":"tr","p":{"a":0,"k":[-7.886,88.719]},"a":{"a":0,"k":[0,0]},"s":{"a":0,"k":[100,100]},"r":{"a":0,"k":0},"o":{"a":0,"k":100},"sk":{"a":0,"k":0},"sa":{"a":0,"k":0},"nm":"T"}],"nm":"R"}],"ip":0,"op":300,"st":0}],"slots":{"gradient_fill":{"p":{"a":0,"k":[0,0.1,0.1,0.2,1,1,0.1,0.2,0.1,1]}}},"markers":[]}
+{"v":"4.8.0","meta":{"g":"LottieFiles AE 3.0.2","a":"","k":"","d":"","tc":""},"fr":60,"ip":0,"op":121,"w":550,"h":550,"nm":"C","assets":[],"layers":[{"ind":1,"ty":4,"nm":"S","sr":1,"ks":{"o":{"a":0,"k":100},"r":{"a":1,"k":[{"i":{"x":[0.833],"y":[0.833]},"o":{"x":[0.167],"y":[0.167]},"t":0,"s":[0]},{"t":120,"s":[360]}]},"p":{"a":0,"k":[275,275,0]},"a":{"a":0,"k":[-7.886,88.719,0]},"s":{"a":0,"k":[100,100,100]}},"ao":0,"shapes":[{"ty":"gr","it":[{"ty":"rc","d":1,"s":{"a":0,"k":[282.019,134.888]},"p":{"a":0,"k":[0,0]},"r":{"a":0,"k":0},"nm":"R"},{"ty":"st","c":{"a":0,"k":[0.991,0,1,1]},"o":{"a":0,"k":100},"w":{"a":0,"k":3},"lc":1,"lj":1,"ml":4,"nm":"S"},{"ty":"gf","o":{"a":0,"k":100},"r":1,"g":{"p":9,"k":{"a":0,"k":[0,0.514,0.373,0.984,0.141,0.478,0.412,0.984,0.283,0.443,0.451,0.984,0.379,0.408,0.49,0.984,0.475,0.373,0.529,0.984,0.606,0.278,0.647,0.925,0.737,0.184,0.765,0.867,0.868,0.092,0.882,0.808,1,0,1,0.749]},"sid":"gradient_fill"},"s":{"a":0,"k":[-159.51,23.531]},"e":{"a":0,"k":[183.084,8.059]},"t":1,"nm":"G"},{"ty":"tr","p":{"a":0,"k":[-7.886,88.719]},"a":{"a":0,"k":[0,0]},"s":{"a":0,"k":[100,100]},"r":{"a":0,"k":0},"o":{"a":0,"k":100},"sk":{"a":0,"k":0},"sa":{"a":0,"k":0},"nm":"T"}],"nm":"R"}],"ip":0,"op":300,"st":0}],"slots":{"gradient_fill":{"p":{"a":0,"k":[0,0.1,0.1,0.2,1,1,0.1,0.2,0.1,1]}}},"markers":[]}

test/testLottie.cpp

@@ -44,7 +44,7 @@ TEST_CASE("Lottie Slot", "[tvgLottie]")
     auto picture = animation->picture();
     REQUIRE(picture->type() == Type::Picture);
 
-    const char* slotJson = R"({"gradient_fill":{"p":{"a":0,"k":[0,0.1,0.1,0.2,1,1,0.1,0.2,0.1,1]}}})";
+    const char* slotJson = R"({"gradient_fill":{"p":{"p":2,"k":{"a":0,"k":[0,0.1,0.1,0.2,1,1,0.1,0.2,0.1,1]}}}})";
 
     //Slot override before loaded
     REQUIRE(animation->override(slotJson) == Result::InsufficientCondition);