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--- public:t-gede-14-1:lab8 [2014/03/10 17:15] – [Discussion] marino
+++ public:t-gede-14-1:lab8 [2024/04/29 13:33] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
 ====== LAB8: Particle Systems ======
-In this lab we will be checking out particle systems, This lab will be based on the "The Ogre 3D Startup Sequence" from the book "Ogre 3D 1.7 - Beginner's Guide" by Felix Kerger, Chapter 10.
+In this lab we will be checking out particle systems, This lab will be roughly based on the "The Ogre 3D Startup Sequence" from the book "Ogre 3D 1.7 - Beginner's Guide" by Felix Kerger, Chapter 10.
@@ Line 8: / Line 8: @@
 Discussion thread for this lab is here: [[https://piazza.com/class/hq7dlipqggr2qe?cid=34|Lab 8 Discussion Thread]]
+===== Preperation =====
+You will have to create the folder ''ParticleSystems'' where your application can see it. and add the folder into your resource file like you have done in previous labs.
+You can use your own project or start fresh with the base application {{:public:t-gede-14-1:lab6_handout.7z|code}}
+===== Lab =====
   - **Add the following code your MyApplication::createScene function** Here we are creating a particle system from the given examples that come with the ogre sdk, and attaching it to our Sinbad model. \\ You should see a "fireish" thingamajing emitting from the head of Sinbad. <code cpp>// Create a particle system
 Ogre::ParticleSystem* partSystem = _sceneManager->createParticleSystem("smoke", "Examples/Smoke");
@@ Line 21: / Line 25: @@
 	// Make the emitter limit the emitter to have at maximum 500 particles active.
 	// And set the particle type as point, which always faces the camera.
-	quota				500
+	quota			500
 	billboard_type		point
 	// Make the emitters origin a point.
 	emitter Point {
 		// Make the emitter emit 3 particles per second.
-		emission_rate	3
+		emission_rate		3
 		// Emitt the particles in the given direction, at a velocity of 20 units per second.
 		direction		1 0 0
@@ Line 32: / Line 36: @@
 	}
 }</code>
-  - **Now add additional properties to the Emitter**, Now lets make the particle emitter shoot the particles in a random fashion, and destroy them after 10 seconds alive. Additionally we will color them red. <code cpp>
+  - **Now add additional properties to the Emitter**, Now lets make the particle emitter shoot the particles in a random fashion, and destroy them after 10 seconds alive. Additionally we will colour them red. <code cpp>
-// This will be the range of angle varialtion the particles will be fired at.
+// This will be the range of angle variation the particles will be fired at.
 angle			30
 // Destroy the particle after 10 seconds.
-time_to_live	10
+time_to_live		10
 // Colour the particles red with a fully opaque alpha value.
 Colour			1 0 0 1</code>
-  - **Now we will add some Additional variation** Lets make the time to live random, and give them colour a certain range. We do that by chaning the time_to_live and colour attributes in the emitter block. Also change the emission rate to 30 increasing the rate of which the particles spawn. <code cpp>// Destroy the particle after 1 to 4 seconds.
+  - **Now we will add some Additional variation** Lets make the time to live random, and give them colour a certain range. We do that by changing the time_to_live and colour attributes in the emitter block. Also change the emission rate to 30 increasing the rate of which the particles spawn. <code cpp>// Destroy the particle after 1 to 4 seconds.
 time_to_live_min	1
 time_to_live_max	10
@@ Line 45: / Line 49: @@
 colour_range_start	1 0 0
 colour_range_end	0 0 1</code>
-  - **Additional attributes,** Now remove all the addition lines added from the particle emitter leaving only the emission_rate, direction and velocity. And we will now modify the behaviour of the emitter, giving it a emission duration and restart delay. Lets make it emitt particles for 1 second and then stop for one second before starting again. <code cpp>// Emitt particles for 1 second at a time with a 1 second interval.
+  - **Additional attributes,** Now remove all the additional lines added in the previous steps from the particle emitter leaving only the ''emission_rate, direction and velocity''. And we will now modify the behaviour of the emitter, giving it a emission duration and restart delay. Lets make it emit particles for 1 second and then stop for one second before starting again. <code cpp>// Emit particles for 1 second at a time with a 1 second interval.
 duration 		1
-repeat_delay	1</code>
+repeat_delay		1</code>
   - **Adding affectors** Now we will explore particle system affectors: Remove the attributes added in the last step. leaving again, only the ''emission rate, velocity and direction''. And set the ''time_to_live 10''. See: [[http://www.ogre3d.org/docs/manual/manual_40.html#DeflectorPlane-Affector|Affector Reference]].
     - **Scaling affector:** Add the following line to the particle_system block, this will scale the particles by the given value per second : <code cpp>affector Scaler {
-	rate 10
+	rate 	10
 }</code>
-    - **Color fading affector** Color affector will add the given values from the particle color. To use it replace the scalar affector with: <code cpp>// This affector will add the folloving values to the colour of the particles each second.þ
+    - **Colour fading affector** Colour affector will add the given values to the particle colour. To use it replace the scalar affector with: <code cpp>// This affector will add the following values to the colour of the particles each second.þ
 affector ColourFader {
 	red 	 0.0
@@ Line 73: / Line 77: @@
 	alpha2  -1
 }</code>
-    - And finally we have probably the most useful tool, called the ColorInterpelator. it works simularly to the ColorFader2 but with 1..6 number of states. It is used quite differently though. You proide the time on scale from 0-1 ''time# scale'' , and colours are given in the form ''colour# r g b a''.  Lets create a happy stream: <code cpp>// on ColourInterpolators you can have up to 6 colour intervals.
+    - And finally we have the ColorInterpelator. It works similarly to the ColorFader2 but with 1..6 number of states. It is used quite differently though. You provide the time on scale from 0-1 ''time# scale'' , and colours are given in the form ''colour# r g b a''.  Lets create a jolly little stream: <code cpp>// ColourInterpolators can have up to 6 colour intervals indexed 0 to 5.
 affector ColourInterpolator {
 	time0 0
@@ Line 92: / Line 96: @@
 	time5 1
 	colour5 0 1 0 0
-}</code> **Note: **You have to define the defult colour as ''colour 1 0 0 0'' in the point_emitter block to eliminate the stuttering when the particles spawn. Just remember to remove that for the next step.
+}</code> **Note: **You have to define the default colour as ''colour 1 0 0 0'' in the point_emitter block to eliminate the stuttering when the particles spawn. Just remember to remove that for the next step.
-  - **Direction Randomiser** We can make the particles change direction at random: <code cpp>// This will make the particles fly around like it has no tomorrow.
+  - **Direction Randomiser** We can make the particles change direction at random: <code cpp>// This will make the particles fly around like they have no tomorrow.
 affector DirectionRandomiser {
 	// This indicates the magnitude of the random choices the particle makes.
-	randomness 1000
+	randomness 	1000
 	// Scope governs the chance that a given particle takes a random direction change scale from 0..1 ~ 0-100%
-	scope 1
+	scope 		1
 	// Here you can indicate if the particle should randomize its velocity or not. <true|false>
 	keep_velocity true
-}</code> This could be useful for a file of fireworks catching fire?, or a crowd of mosquitos
+}</code> This could be useful for a pile of fireworks catching fire?, or a swarm of mosquitoes.
   - **Deflector Planes** Deflector planes can make the particles change direction when they hit the deflector plane, the plane is provided in point normal form. <code cpp>// Deflector planes bounce the particles of the given plane.
 affector DeflectorPlane {
 	//The point of the plane, note: the plane is infinite
-	plane_point 10 0 0
+	plane_point 	10 0 0
 	// The normal vector of the plane, the direction of the particles will be mirror around this normal.
-	plane_normal -0.7 0.7 0
+	plane_normal 	-0.7 0.7 0
 	// The amount of velocity the particles retain after the collision.
-	bounce 1.0
+	bounce 		1.0
 }
 // You can provide more than one plane.
 affector DeflectorPlane {
-	plane_point 10 15 0
+	plane_point 	10 15 0
-	plane_normal -0.7 -0.7 0
+	plane_normal 	-0.7 -0.7 0
-	bounce 1.0
+	bounce 		1.0
 } </code>
   - **Different emitters** We can make the spawn point of the particles different, some of them have different parameters see: [[http://www.ogre3d.org/docs/manual/manual_38.html|Emitters]]
@@ Line 125: / Line 129: @@
     - Hollow Ellipsoid
     - Ring
-  - **Get your hands dirty.** Now create a particle system using the things you have learned. Dont just randomly assign everything to a particle effect, make something :) A fountain, bleeding wound, did Sinbad eat tacos for dinner hint anybody?, where will you be when ** strikes? What I want to see is at least: [[http://www.ogre3d.org/docs/manual/manual_36.html#Particle-Emitters|Any Emitter]], a [[http://www.ogre3d.org/docs/manual/manual_40.html#DeflectorPlane-Affector|DeflectorPlane]], any [[http://www.ogre3d.org/docs/manual/manual_40.html#ColourFader-Affector|Color Changer]], and a [[http://www.ogre3d.org/docs/manual/manual_40.html#Linear-Force-Affector|LinearForce affector]]: // A very simple fountain: {{ :public:t-gede-14-1:ogre_fountain.png?nolink |}}
+  - **Get your hands dirty.** Now create a particle system using the things you have learned. Don't just randomly assign everything to a particle effect, make something :) A fountain, bleeding wound, did Sinbad eat tacos for dinner, hint, anybody?, where will you be when #"/& strikes? What I want to see is at least: [[http://www.ogre3d.org/docs/manual/manual_36.html#Particle-Emitters|Any Emitter]], a [[http://www.ogre3d.org/docs/manual/manual_40.html#DeflectorPlane-Affector|DeflectorPlane]], any [[http://www.ogre3d.org/docs/manual/manual_40.html#ColourFader-Affector|Color Changer]], and a [[http://www.ogre3d.org/docs/manual/manual_40.html#Linear-Force-Affector|LinearForce affector]]: \\ //**A very simple fountain:**// {{ :public:t-gede-14-1:ogre_fountain.png?nolink |}}
 ===== Bonus =====
+<box green 100% | Das Bonus von GEDE!>
+  - **Using particle effects for something swell.** Add a glowing particle effect to Sinbads sword. Particle effects are often used for all sorts of [[https://www.youtube.com/watch?v=yLGWBKDSUVs&index=8&list=PLt5SL2R19SuJCLyqMdHMsfxZWAt0vGk2Q|special effects :)]]. You can use the same command as attaching the sword to the handle bone, just as well to attach a particle generator. //**Hint:** If Sinbad was holding a broom stick, the length of the broom would be the positive Z axis, and the y axis goes up into his arm.//  <code cpp>// Attach a sword to Sinbads right hand.
+// Create the sword entity.
+Ogre::Entity* sword = _sceneManager->createEntity("Sword.mesh");
+// Attach the sword to Sinbads right hand.
+_SinbadEnt->attachObjectToBone("Handle.R", sword);
+// Clasp Sinbads hands around the hilt of the sword.
+_SinbadEnt->getAnimationState("HandsClosed")->setEnabled(true);</code>
+  - **Celebrate Sinbads amazing sword effect.** If you followed the last point then Sinbad is surely a happy seadog, and a happy fellow deserves a show! Create some fireworks using the particle system Ogre provides. //**Hint:** Check out the [[http://www.ogre3d.org/docs/manual/manual_38.html#Emitting-Emitters|Emitter emitters]]. I'll provide you with some skeleton code.// <code cpp>// Use this as a base for your fireworks :)
+particle_system Fireworks {
+	// Make the particles use the "Examples/Flare" material, and be 1x1 units large.
+	material 		Examples/Flare
+	particle_width 		1
+	particle_height		1
+	// Make the emitter limit the emitter to have at maximum 2000 particles active.
+	// And set the particle type as point, which always faces the camera.
+	quota			2000
+	billboard_type		point
+	// The maximum amount of emitter emitters
+	emit_emitter_quota 	10
+	// Make the emitters origin a Point.
+	emitter Point {
+		// tell the particles to emitt the "bomb emitter" described below
+		emit_emitter 		bomb
+		// Fire one firework per second
+		emission_rate		1
+		// Make the particles go up.
+		direction 		0 1 0
+		velocity 		70
+		time_to_live 		2
+	}
+	// The emitter emitted by the particles above
+	emitter Point {
+		// Name the emitter to match the name in the emit_emitter block
+		name 			bomb
+		// Configure the explosion.
+		emission_rate 		200
+		velocity 		30
+		// How long should the firework emit
+		duration_min            0.1
+		duration_max		0.2
+		// This is used to make sure the particles in the emitter emitter dont fire while the particle is in mid flight.
+        repeat_delay_min        1
+        repeat_delay_max        1.9
+        time_to_live_min	0.3
+        time_to_live_max	0.4
+	}
+	// Add some pseudo gravity.
+	affector LinearForce {
+		force_vector 0 -50 0
+	}
+}</code> **Note: ** Affectors affect both the emitter and the emitter emitter :){{ :public:t-gede-14-1:ogre_fireworks.png?nolink |}}
+  - **Lastly** If you come up with a use for the particle system and think that it deserves an additional bonus point or half, then I might be generous :)  \\ **Hint:** You could use the cylindrical effect from Lab 3 for interesting particle system effects :)
+</box>
 ===== When You Are Finished =====
 Upload your **commented source files** into Lab8 in MySchool (zip them up if more than one). The lab projects will not be graded, but their completion counts towards your participation grade.