TutorialDown The Hills
by Conspicuous Switzerland
Welcome to the tutorial „Down the Hills“. First of all, I have to apologize for my bad English. I hope that I will always find the right expressions because English is not my mother tongue. Secondly, I hope you will enjoy the tutorial.
So let‘s start. Open a new blender file, delete the default cube and add a plane in frontview. Scale the plane to about 20. You can view this in the tranform properties (press N). Then subdivide the plane in edit mode about 5 to 8 times.
Now turn the proportional tool on.
Still in edit mode select some vertex or if you like some faces and move them up by pressing G to form the hills. Note: with the scroller you can increase or decrease the size of the circle which will affect the mesh. You need also to consider how the ball will roll down the hills in the end in order to get the hills right. But it ist enough to do it just provisional. Later we will adjust the hills.
So, lets starts with the materials. Add a new material and name it grass. We set up the grass material to index 1 and the dirt material to index 2. So in the edit panel Add a new material index and select the whole mesh and assign it. Back in the material panel rename it to dirt and change the colour to brown.
Set the shaders to Minnaert, Ref 0.8, Dark 1.2 and Phong, Spec 0.4, Hard 40. Then add a new textures and name it „bump“ or whatever you want. Leave the Map Input in its default state. In Map To select Nor and deselect Col. Moreover, set the Nor value to 1.0. Then go to the textures button and select Voronoi as the texture type. Now set the Size to 0.020.
Give the grass a green colour. The shaders are Minnaert, Ref 0.56, Dark 1.26 and Phong, Spec 0.4, Hard 40. The Strands: start 2.0, end 0.5 and the shape 0.0 but you can play around with them.
I suggest selecting the hair strands preview type in order to get a better idea how the grass looks.
Then add three cloud textures as shown in the images.
Now we add a particle system to the object. Go to the object panel and select the particle panel left. Then press the „Add New“ button and choose „Hair“ as the type of the particle system. Increase the size of the particles to about 3000 and leave the default 10 segments. The final density we will reach with children. The Emit From value should be Random. The Initial Velocity in the Normal direction of about 0.22 is enough to give the grass some length.
In the Children tab use Faces from children. Set the amount to 0 and the render amount to 250.
Put the roughness as shown in the images. In the Visualization tab select Emitter and Col and reassure that the Material 1 is active. Also select B-Spline and Strand render. For now that are the settings.
Back in object mode add a new UVSphere. I would suggest you make 32 segments and 32 rings. If you like you can already smooth the sphere. Also you can assign a material and map it if you like. Then place your ball whereever you want to start rolling the ball.
Now it gets a bit complicated. Select your ball and go to the logic panel. As the object type choose Rigid Body and Actor. Adjust the Radius so that it fits your ball. With the Mass and Damp you have to play around a bit later.
Now select your Plane (the hills). Go to the Logic Panel again and choose as the object type Static and Actor. Then open the Text Editor and creating a new Text area.
Change the default Text to „framerate“. Now type the following code:
This will change the game engine default frame rate of 60 frames per second to 25 as the default frame rate in Blender is.
Back in the Logic button and still the Plane selected, associate an Always sensor and a Phyton controller with the object in the game. Type „framerate“ into the script. So lets start with the Game Engine.
In obeject mode press P to start the game engine. The ball should roll down the hills. Now it is time to consider how your animation should look like in the end. If you want that the ball stops in front of your camera then position your camera where you want it. By changing your hills and also the Mass and Damp in the game logic button of the ball you can affect the ball movements. After changing always test them with pressing P and see how the ball moves.
If you are satisfied with the ball running down the hills you have to turn on the „Record Game Physics to IPO“ in the Game Tab in the Header. Now run the Game Engine again. If you know open the IPO Editor you should see the recorded data.
To finish up, we add a soft body modifier to the hills as shown in the image.
Then the ball you add a collision modifier as shwon in the image.
Now you can bake your scene by simply pressing the Bake button in the collision tab of the hills object. The grass should now bend down.
The last thing is setting up the lamps and render the whole animation.
Thanks for reading my little tutorial „Ball down the hills“. I hope you have enjoyed it and that you now have a nice ball rolling down the hills.