From cbb6e7a04f7cf4cb0f719f8b94ccef1ad4382e3b Mon Sep 17 00:00:00 2001
From: Stiffly <adambylehn@hotmail.com>
Date: Wed, 14 Oct 2015 17:40:24 +0200
Subject: [PATCH] Trail to individual brick debris.

Counter the particle spawn bug.
The bug occurs when the position is read as (0, 0) from the emitter. Similar particle removal bug appears when particles are deleted. Counterered  by deleting particle entities a little time before b2particles.
---
 src/game/Game/LevelSystem.cpp      | 19 +++++++++++++++++++
 src/game/Physics/PhysicsSystem.cpp | 22 ++++++++++++++--------
 2 files changed, 33 insertions(+), 8 deletions(-)

diff --git a/src/game/Game/LevelSystem.cpp b/src/game/Game/LevelSystem.cpp
index cc1510e..6868b88 100755
--- a/src/game/Game/LevelSystem.cpp
+++ b/src/game/Game/LevelSystem.cpp
@@ -394,6 +394,25 @@ void dd::Systems::LevelSystem::BrickHit(EntityID entityHitter, EntityID entityBr
 		m_World->RemoveComponent<Components::Template>(b);
 		m_World->SetEntityParent(b, 0);
 		m_World->CommitEntity(b);
+
+		//Particle trail
+		Events::CreateParticleSequence p;
+		p.parent = b;
+		p.AlphaValues.push_back(1.f);
+		p.AlphaValues.push_back(0.f);
+		p.RadiusValues.push_back(0.06f);
+		p.RadiusValues.push_back(0.f);
+		p.RadiusDistribution = 1;
+		p.EmitterLifeTime = 2.f;
+		p.ParticleLifeTime = 1.f;
+		p.ParticlesPerTick = 1;
+		p.SpawnRate = 0.1f;
+		p.Speed = 10.f;
+		p.EmittingAngle = glm::half_pi<float>();
+		p.SpriteFile = "Textures/Particles/FadeBall.png";
+		p.Color = brickModel->Color;
+		//p.Spread = ...
+		EventBroker->Publish(p);
 	}
 
 
diff --git a/src/game/Physics/PhysicsSystem.cpp b/src/game/Physics/PhysicsSystem.cpp
index 676c6b9..d2d0c63 100755
--- a/src/game/Physics/PhysicsSystem.cpp
+++ b/src/game/Physics/PhysicsSystem.cpp
@@ -268,7 +268,7 @@ void dd::Systems::PhysicsSystem::UpdateEntity(double dt, EntityID entity, Entity
         }
 		//Update alpha
 		auto sprite = m_World->GetComponent<Components::Sprite>(entity);
-		float timeProgress = particle->TimeLived / particle->LifeTime;
+		float timeProgress = particle->TimeLived / (particle->LifeTime - 0.1);
 		if (timeProgress > particle->LifeTime) {
 			timeProgress = particle->LifeTime;
 		}
@@ -305,10 +305,11 @@ float dd::Systems::PhysicsSystem::ScalarInterpolation(float timeProgress, std::v
 		return spectrum[0];
 	}
 
-	float dValue = glm::abs(spectrum[0] - spectrum[1]);
-	if (spectrum[0] > spectrum[1]) {
-		dValue *= -1;
-	}
+	float dValue = spectrum[1] - spectrum[0];
+//	glm::abs(spectrum[0] - spectrum[1]);
+// 	if (spectrum[0] > spectrum[1]) {
+// 		dValue *= -1;
+// 	}
 
 	float scalar = spectrum[0] + dValue * timeProgress;
 
@@ -514,12 +515,18 @@ void dd::Systems::PhysicsSystem::UpdateParticleEmitters(double dt)
 
 		//Create new particle
         for ( int j = 0; j < emitter->ParticlesPerTick; j++) {
+			b2ParticleDef particleDef;
+			//position
+			particleDef.position = b2Vec2(emitterTransform->Position.x, emitterTransform->Position.y);
+			if (particleDef.position.x == 0.f && particleDef.position.y == 0.f) {
+				continue;
+			}
+
 			auto particle = m_World->CloneEntity(pt, 0);
 			m_World->RemoveComponent<Components::Template>(particle);
 			auto particleTransform = m_World->GetComponent<Components::Transform>(particle);
 			auto particleComponent = m_World->GetComponent<Components::Particle>(particle);
 
-			b2ParticleDef particleDef;
             particleDef.flags = particleTemplate->Flags;
             //particleDef.color TODO: Implement this if we want color mixing and shit.
             particleDef.lifetime = particleTemplate->LifeTime;
@@ -537,8 +544,7 @@ void dd::Systems::PhysicsSystem::UpdateParticleEmitters(double dt)
 			glm::vec2 vel = unitVec * emitter->Speed * (float)dt * speedMultiplier;
             particleDef.velocity = b2Vec2(vel.x, vel.y);
 
-			//position
-			particleDef.position = b2Vec2(emitterTransform->Position.x, emitterTransform->Position.y);
+			
 
 			//radius - currently not working :j
 			float radius = emitter->RadiusValues[0];