New unit tests around GetMaxFrame / GetMaxTime. Improvemetns to apply_json_to_timeline() to not clear all cache when setting the timeline's "duration" - an optimization for performance

Author: jonoomph

src/Timeline.cpp

@@ -1526,6 +1526,7 @@ void Timeline::apply_json_to_effects(Json::Value change, EffectBase* existing_ef
 
 // Apply JSON diff to timeline properties
 void Timeline::apply_json_to_timeline(Json::Value change) {
+    bool cache_dirty = true;
 
 	// Get key and type of change
 	std::string change_type = change["type"].asString();
@@ -1534,9 +1535,6 @@ void Timeline::apply_json_to_timeline(Json::Value change) {
 	if (change["key"].size() >= 2)
 		sub_key = change["key"][(uint)1].asString();
 
-	// Clear entire cache
-	ClearAllCache();
-
 	// Determine type of change operation
 	if (change_type == "insert" || change_type == "update") {
 
@@ -1558,6 +1556,9 @@ void Timeline::apply_json_to_timeline(Json::Value change) {
 			// Update duration of timeline
 			info.duration = change["value"].asDouble();
 			info.video_length = info.fps.ToFloat() * info.duration;
+
+			// We don't want to clear cache for duration adjustments
+            cache_dirty = false;
 		}
 		else if (root_key == "width") {
 			// Set width
@@ -1645,6 +1646,10 @@ void Timeline::apply_json_to_timeline(Json::Value change) {
 
 	}
 
+	if (cache_dirty) {
+        // Clear entire cache
+        ClearAllCache();
+	}
 }
 
 // Clear all caches

tests/Timeline.cpp

@@ -607,6 +607,7 @@ TEST_CASE( "GetMaxFrame and GetMaxTime", "[libopenshot][timeline]" )
 	std::stringstream path1;
 	path1 << TEST_MEDIA_PATH << "interlaced.png";
 	Clip clip1(path1.str());
+    clip1.Id("C1");
 	clip1.Layer(1);
 	clip1.Position(50);
 	clip1.End(45);
@@ -616,6 +617,7 @@ TEST_CASE( "GetMaxFrame and GetMaxTime", "[libopenshot][timeline]" )
 	CHECK(t.GetMaxFrame() == 95 * 30 + 1);
 
 	Clip clip2(path1.str());
+	clip2.Id("C2");
 	clip2.Layer(2);
 	clip2.Position(0);
 	clip2.End(55);
@@ -640,6 +642,22 @@ TEST_CASE( "GetMaxFrame and GetMaxTime", "[libopenshot][timeline]" )
 	t.RemoveClip(&clip1);
 	CHECK(t.GetMaxFrame() == 115 * 30 + 1);
 	CHECK(t.GetMaxTime() == Approx(115.0).margin(0.001));
+
+    // Update Clip's basic properties with JSON Diff
+    std::stringstream json_change1;
+    json_change1 << "[{\"type\":\"update\",\"key\":[\"clips\",{\"id\":\"C2\"}],\"value\":{\"id\":\"C2\",\"layer\":4000000,\"position\":0.0,\"start\":0,\"end\":10},\"partial\":false}]";
+    t.ApplyJsonDiff(json_change1.str());
+
+    CHECK(t.GetMaxFrame() == 10 * 30 + 1);
+    CHECK(t.GetMaxTime() == Approx(10.0).margin(0.001));
+
+    // Insert NEW Clip with JSON Diff
+    std::stringstream json_change2;
+    json_change2 << "[{\"type\":\"insert\",\"key\":[\"clips\"],\"value\":{\"id\":\"C3\",\"layer\":4000000,\"position\":10.0,\"start\":0,\"end\":10,\"reader\":{\"acodec\":\"\",\"audio_bit_rate\":0,\"audio_stream_index\":-1,\"audio_timebase\":{\"den\":1,\"num\":1},\"channel_layout\":4,\"channels\":0,\"display_ratio\":{\"den\":1,\"num\":1},\"duration\":3600.0,\"file_size\":\"160000\",\"fps\":{\"den\":1,\"num\":30},\"has_audio\":false,\"has_single_image\":true,\"has_video\":true,\"height\":200,\"interlaced_frame\":false,\"metadata\":{},\"path\":\"" << path1.str() << "\",\"pixel_format\":-1,\"pixel_ratio\":{\"den\":1,\"num\":1},\"sample_rate\":0,\"top_field_first\":true,\"type\":\"QtImageReader\",\"vcodec\":\"\",\"video_bit_rate\":0,\"video_length\":\"108000\",\"video_stream_index\":-1,\"video_timebase\":{\"den\":30,\"num\":1},\"width\":200}},\"partial\":false}]";
+    t.ApplyJsonDiff(json_change2.str());
+
+    CHECK(t.GetMaxFrame() == 20 * 30 + 1);
+    CHECK(t.GetMaxTime() == Approx(20.0).margin(0.001));
 }
 
 TEST_CASE( "Multi-threaded Timeline GetFrame", "[libopenshot][timeline]" )