Blender Seascape Tutorial

Transcription

1 Blender Seascape Tutorial The Magic of Textures in Blender 2.32 By COG a.k.a Colin Litster Areas Covered This tutorial will show you how I created a seascape scene via Blender for an animated short I am making called Cog. As there are billions of waves in the oceans there are many ways to achieve a sea scene within Blender. I have attempted to use only in-built tools of Blender 2.32 to achieve a realistic effect. I did it this way to help me learn Blender as much as anything and this is very much the way I approaching my film i.e., I am using the film to force my learning of Blender and Blender to help me achieve the film. Prerequisites You should have a minimum understanding of creating, scaling moving and rotating objects in Blender. How to create a Material and add textures. The Blender 2.3 manual is the best place to learn these fundamental skills. Some understanding of IPOs although I do give a brief explanation in relation to materials in the text. As the seascape was produced in Blender 2.32 and all my screen shots and explanations are from Blender 2.32 I would suggest that you use this version. However, it should be possible to apply the techniques to previous versions as well.. If you intend to render to my example sizes, particularly a full size animation, be prepared for some long renderings. There are multiple transparencies, 3D clouds and the need to use Blenders unified renderer which will mean loooooooooooong renders. Researching Inspiration As with any 3D creation, particularly one requiring detailed textures, research and observation will save you an enormous amount of time fiddling in any 3D application for inspiration can waste an enormous amount of time. For my project I visited the local library to view art books by famous naval watercolour artists such as John Salmon, R.B. Spencer, and others Of course if you are near the sea go out and stare at it for several hours. Examine what s happening with the wave motion. Ask yourself how many layers of wave are there and what s their speed? What colour is the sea? What is floating on the surface i.e. seaweed, foam from the waves, debris? How is this effected by any of the other things. For me it came down to a few fundamental things that I would need to work on within Blender. If these are correct then small fine tuning should produce the effect I wanted. Colour o A dark moody green. Taken straight from a watercolour in the library book. Page 1 of 41 Created by Colin Litster April 2004

2 Depth Transparency o The water has transparency and its colour will change with wave thickness and distance. Once again I used the examples from the library books to determine the colours. NOTE: Nothing to stop you scanning the pictures to your favourite paint program and getting the RGB values directly. You will need to convert the values to Blenders 0-1. Timing (creating realistic wave motion) o At least 3 levels of wave, 2 main wave fronts travelling quite fast as it s a storm and interacting with each other to produce a random wave motion. And a much smaller wave acting quickly on the larger waves. Dirt and Debris o Here I was interested in producing foam that is small bubbles, which therefore exist under the water as well as on top. So that means a dynamic foam effect that alters in depth Z axis and motion X or Y axis. Lighting o My story also required a night time scene or at least a dark moody atmosphere. I knew that would help hide some of the inevitable texture shortcuts necessary. Exercise Have a go at developing your own fundamental scene descriptors such as colour ect. Go to the library and find some books with good photos or illustrations by Naval artists. You can also research via google for inspiration. Scan some of these and examine the colours in your favourite paint program. Make a note of the R,G,B values for the overall sea colour, transparent sea colour, foam colour and any other variation. Work out a way of converting these (0-255) values to Blender R,G,B (0-1) values. See what they look like in Blender compared to the original illustrations. TIP render several simple planes with each of the colour settings from an overhead camera position. If you can t get the lighting correct make each of the materials shadeless. Use both the default renderer and also the Unified renderer and note any differences. By doing this you will have saved yourself an enormous amount of time. Using any 3D program to experiment with colour will take forever. Rendering takes time and small renders give little idea of what the final result will be. At least this way you will be half way there before you start rendering. Lets get started Start a new scene in Blender Scale the Mesh not the Object In the top view add a mesh plane While you are still in mesh edit mode scale the plane so that it is approximately 7 grid units square Page 2 of 41 Created by Colin Litster April 2004

3 SKEY Scale, CTRL+ LMB while moving the mouse until the plane conforms to approximately 7 grid squares from the centre. The reason for doing this, rather than just scaling using the numeric entry in object mode, is that the local dimensions will remain as 1 which will make the wave creation easier. Subdivide the mesh TAB to get into mesh edit mode and make sure the default 4 vertices are selected AKEY toggles between all and none NOTE: I m sure you know that yellow highlighted vertices are selected so I won t say again. Press the WKEY and select subdivide. Do this six times to produce enough vertices for the wave effect to give a descent result. Set the mesh smooth Place a camera Move the default camera to the following location Page 3 of 41 Created by Colin Litster April 2004

4 Press F9 with the camera selected and change the Lens of the Camera to 67. Page 4 of 41 Created by Colin Litster April 2004

5 Set one of the windows to the camera view. Move the cursor over the view and press the 0KEY on the numeric keyboard. You can also set it from the view menu of the window. The reason for doing this is that you will be able to see the wave effect before we complicate the scene with materials. It also allows us to see the wave effect in the camera view without having to render at this stage. That can save you a lot of time. SAVE YOUR WORK HERE WAVES in Blender I ve always wanted to find out more about this effect but couldn t find much info other than what s in the documentation and the new manual. To be frank I found it difficult to understand wave width equals 4 over narrow in any real sense. I just want it to look right, so I have to admit that my approach was to set it up visually and adjust until it looked right. In particular I have not found an easy way to create a cyclic set of waves that repeat over a given range of frames. If there is some magic formula for that please let me know. WAVE Effect To create a WAVE effect make sure the plane is selected and press F7 for the Constraints panel. Select effects tab and NEW Effect. In the button that says Build LMB and from the displayed options select Wave. Page 5 of 41 Created by Colin Litster April 2004

6 Enter the following settings The Sta x: and Sta y: are the starting point of our wave in the local mesh co-ordinates The larger X Y and Cycl buttons should be selected for this example as it will give a large ripple (circular wave) with multiple pulses. The speed setting should be low or the wave will be unrealistic. Page 6 of 41 Created by Colin Litster April 2004

7 The height, width, and narrow were arrived at by experimentation. Lastly the Time start. Lifetime, and Damptime buttons have been set to give the best continuous movement of our waves over the 250 frames I am using in the example. By the way the Damptime cannot be reduced below 10. Review You can see the effect of this wave on the plane by putting the mouse cursor in the camera view and pressing ALTA. This can save you time as you don t need any special lighting or long renders to see the wave effect. Its best to view this in wireframe mode so if your waves just looks black press ZKEY to switch to wire view. Not bad but we can add some more randomness to our ocean. Press ESC to stop the preview animation. Setting a second wave front Go back to the Constraints panel and select the NEW Effect button again. A second identical wave effect is created. Modify the settings as shown. Here we have modified the starting location and some of the wave settings so that when the 2 waves interact they produce a more random motion. Page 7 of 41 Created by Colin Litster April 2004

8 Review the 2 waves ALTA in the camera window and ESC when you are satisfied. IMPORTANT NOTE Create the waves in this order or the effect will be very different. Waves act on each other in the order that they are created. SAVE YOUR WORK HERE Page 8 of 41 Created by Colin Litster April 2004

9 Creating a proto-ocean Well so far we have a pond rather than an ocean. Time to use Blender modelling tricks to enlarge our ocean. To do this it is easiest to work from a top view window. If you have one in your blender setup make it active, by moving your mouse pointer into the window and press CTRL+UP arrow to make it full screen. NOTE: number pad 7 will switch the active view to TOP. Adjust the view by panning and zooming until the plane is in the bottom right side of the screen. We will now copy and mirror the plane to produce an ocean four times as big. With the plane selected press ALTD (this produces a linked copy of the plane). You are in grab mode so if you move the mouse the copied plane will also move. DON T click the LMB yet. Hold CTRL while you move the mouse to restrict movements to the grid. Move the copied plane so that it aligns its right-side to the original planes left side. Repeat the process and move the third copy to the top of the second copy. And one more time to complete the 4 square ocean. Page 9 of 41 Created by Colin Litster April 2004

10 If you switch back to your camera view and ALTA to preview you will notice that the waves are not in sync between planes. Page 10 of 41 Created by Colin Litster April 2004

11 What we need to do is correctly mirror each of the copied planes to the first. The easiest way to do this is via the numeric input screen. Select the bottom left-hand corner plane in the top or camera view. That s the first copy that we made. Press NKEY to bring up the numeric entry pad and alter the size X value to negative. Select the top-left plane and alter its size X and Y to negative values. Lastly select the top-right and alter its size Y value to negative. Page 11 of 41 Created by Colin Litster April 2004

12 Using this same technique you can copy and mirror further planes to increase the size of your ocean. You may want to limit the number in your blend file to just those that will be in shot. However, I have had at least 24 with no problems at all. OK time to move onto the all important material and textures. SAVE YOUR WORK HERE Page 12 of 41 Created by Colin Litster April 2004

13 Animated Procedural Textures in Blender In order to make this simple I decided to limit my textures to the inbuilt procedural ones available in Blender Cloud Marble Wood, ect. However, how can these be used to simulate various smaller waves, foam, transparency and depth? Well one of the neat features in Blender is the ability to apply animated movement and size to materials as well as objects. This is achieved using material IPO curves. It is also possible to animate the alpha channel, colour and many other material and texture effects using IPO curves. If you have never seen or used this before I have another Tutorial available from my website. Material and texture for the seascape Reload your saved seascape.blend file if it is not loaded already Lets reposition the camera and set up some lights Set the camera to the following location. Now create a spotlight at the following location and rotation. Page 13 of 41 Created by Colin Litster April 2004

14 In the lamp material settings F5 leave the defaults apart from the SpotSi and SpotBl settings which should be altered as follows. Page 14 of 41 Created by Colin Litster April 2004

15 We need just a few more lamps to add some depth and shape to the waves so create 3 lamps, with default settings, at the following locations 1. X = , Y = 3.029, Z = X = 0.000, Y = , Z = X = , Y = , Z = More lights will be added later to give lightning strikes and to add some dimension to the distant waves. However, before we can render anything useful we need a material on our wave geometry. Colour One of the first things to do is set the overall colour of our water. I said earlier that I had found a sea colour I liked from an old navel water colour. The Col values were R 0.00, G 0.282, and B Spe(cularity col) and Mir(ror col) have been set to pure white. There is an advantage to this as it is a simple matter to alter the colour of the wave just by changing the Col RGB values. Specularity (shininess) Also set the Ref(lection) value to and the Spec(ularity value to and finally the hard(ness) value to 138 Page 15 of 41 Created by Colin Litster April 2004

16 Render the scene with this material H mm, looks like very dark green plastic rather than salty water. Lets break that surface up a little with some smaller waves created with a bump map. Press F6 to bring up the texture button then create a cloud texture as shown. Name it Small Waves. Page 16 of 41 Created by Colin Litster April 2004

17 NOTE: Rename the texture by LMB in the TE: area and type SMALL WAVES. Do this with all the textures you create to make them easier to identify. Normal (Bumpiness) Return to the material button press F5 and select the Map To panel and set the texture as NOR(mal) (This button has 3 settings, OFF, Positive BUMP, Negative BUMP. Ensure that it is set as positive BUMP which will produce nice small ripples on our large waves. Set the Nor value to Page 17 of 41 Created by Colin Litster April 2004

18 Select Map Input and change the size X,Y and Z values to 50. Altering the size value here will affect only the size and not the shape of the bump. Press F12 to render the waves at this stage. Page 18 of 41 Created by Colin Litster April 2004

19 A lot better and later when we add movement they will look much more realistic. Alpha (Transparency) Observation is always the key to recreating a real material. I had noticed from my research that water and particularly sea reveals a lot of its appearance through subtle transparencies. This helps give the depth or 3D nature of water. However, this transparency can be very subtle and change over distance and time. Just making our material transparent won t create a very good effect as the Page 19 of 41 Created by Colin Litster April 2004

20 waves will just become darker because there is nothing behind them to show through any transparency. So let s setup a background to show through. Press F8 to bring up the shading context and World sub-context. And enter the values shown. We have set the overall colour to a RED so that you can clearly see the transparency when it is created. We will change the colour to a more pleasing one in a moment. You will also note that a texture has been added to this world material. World materials allow up to 6 textures. In our example a simple Cloud texture is subtracted from our overall colour. Just use the default settings for this cloud texture. But make sure the settings highlighted above are set. RENDER a still image Page 20 of 41 Created by Colin Litster April 2004

21 OK let s start by adding a simple transparency to the ocean mesh. Select RMB the nearest ocean plane. Any changes we make to this will be reflected in all other copied planes because of the way they were copied i.e. ALT-D Data-linked-duplicate. Press F6 to bring up the Texture context and add a new texture to the next available slot. This is a simple diagonal Blend texture from black to white. Page 21 of 41 Created by Colin Litster April 2004

22 Press F5 and in the materials context set the Map To as follows. The Alpha button has 3 settings just like the Nor button. Off, Positive Alpha, negative Alpha. Ours is the second Positive Alpha. Also note that the Mul(tiply) button is on. This will give the transparency required. RENDER a still. Page 22 of 41 Created by Colin Litster April 2004

23 You can see that there is a very subtle transparency nearest the camera and because our ocean plane is copied and mirrored in the distance these subtle transparencies are repeated but it looks random. Let s add another Alpha Texture to our ocean. With the ocean plane still selected press F6 to bring up the Texture context and add a new texture in the next available slot. Page 23 of 41 Created by Colin Litster April 2004

24 A simple Soft noise marble texture. Press F5 for the material context and Map To as follows Here we have used both the Alpha and Translu buttons together with Neg and Mix. The Alpha and Translu buttons are three phase whilst Neg and Mix are either on or off. You can produce exactly the same result with Neg off but would need to toggle the Alpha and Translu buttons. It s much easier to render a few still frames with the variations of the buttons and choose the best. Anyway set it from the figure above and you should be fine. RENDER a still Page 24 of 41 Created by Colin Litster April 2004

25 OK by now you should have got the idea, so let s change the background to a more usable colour for the transparent areas. Press F8 for the world context and change the HoR to Page 25 of 41 Created by Colin Litster April 2004

26 RENDER a still. Page 26 of 41 Created by Colin Litster April 2004

27 Eventually we will animate these textures via IPO curves. SAVE YOUR WORK SO FAR. Adding some Foam Creating foam in a 3D package can be quite difficult. You could perhaps use particles but the rendering would be very long and quite difficult to control. I would much rather think of a texture based solution because that will save valuable time and disk space. With the ocean plane selected press F6 to bring up the Texture Context. In the next vacant texture slot create a marble texture with the following settings. Press F5 to bring up the Material context and alter the Map To settings as follows. Page 27 of 41 Created by Colin Litster April 2004

28 This just mixes a white colour onto our waves. The Neg switch is important because of the way it interprets the texture we created. If this were off then we would have a thin black line on full white foam which would make the waves too bright. In other words the Neg switch will keep the same colour shown i.e. white but reverses what part of the texture will be white. RENDER a still. Page 28 of 41 Created by Colin Litster April 2004

29 Not bad, but now its time to add the Unified Renderer to our output. This offers a much better render where transparencies or alpha channels are used. It is slower but the results are much better. Press F10 and select the Unified Renderer button and then render a still. Page 29 of 41 Created by Colin Litster April 2004

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31 The results may seem not too different from the default render but look at these two close-ups and compare. Page 31 of 41 Created by Colin Litster April 2004

32 DEFAULT RENDERER UNIFIED RENDERER There is much more colour and transparency detail from the Unified Renderer One more wave map When I was working on the seascape, comparing the differences in render quality, I noticed that the small wave looked a little unrealistic so add another to break it up Page 32 of 41 Created by Colin Litster April 2004

33 With the ocean plane selected press F5 to bring up the material context and select the Texture sub-context menu. Select the original cloud texture, slot 0, and copy it to the buffer using the highlighted button. Move to the next available texture slot and paste the copied texture to this location. Also if the number of texture users is 2 click the highlighted button to make it unique to this texture slot. This ensures that we are able to make further changes to the texture later that will not affect the small wave s texture. Switch to the Map Input tab and change the Scale X and Y to 100. Page 33 of 41 Created by Colin Litster April 2004

34 This will actually give us a tiny wave over the top of the small wave. Finally switch to the Map To tab and set Nor and Spec and the Norm value shown. This is another detail of the area in the last render to show the change. Page 34 of 41 Created by Colin Litster April 2004

35 SAVE YOUR WORK Adding the Magic Blender comes into its own when you animate a scene and with our seascape example the added magic to bring it to life is animation of both the wave effect and also the textures. If you have never used material IPOs to achieve texture animation I have a separate tutorial that explains the principles and has an exercise to try. For this exercise I will explain the first Texture IPO procedure but leave you to apply the other texture IPOs yourself. Material IPO curves (Moving textures) Material IPOs work just like any other IPO in Blender. An IPO is created with at least a starting and end point for anyone of the variables available. Blender will then interpret between these points to produce a smooth movement or change over the duration of the animation. Texture IPOs have there own variables that are specific to textures. Reload the seascape.blend file if it is not loaded. In a spare view select the IPO context menu Page 35 of 41 Created by Colin Litster April 2004

36 and switch the sub-context to material. Page 36 of 41 Created by Colin Litster April 2004

37 Next to this box is the number of the texture slot that the IPO will be applied to. Ensure it is set to 0, the small wave texture. By selecting from the right panel of the IPO menu one of the variable label you can directly enter values on the grid with CRL+LMB. However, you can also enter values in the material Map Input tab and press IKEY on relevant frame numbers to enter values. Small Waves For our small wave select the OfsZ variable in the IPO view and enter two control points on the IPO grid of at frame 0 and at frame 250. Because you want a constant speed we must change the curve to a straight line rather than the default smooth curve. Select Curve and from the menu select Extended Mode and Extrapolation. Your curve will now be constant throughout the animation. Noise ~ Texture slot 2 This has one variation over the Y offset. OfsY, at frame 1 and at frame 250 Page 37 of 41 Created by Colin Litster April 2004

38 If you want a little more variability in this texture you could add an OfsZ as well. Foam ~ Texture slot 3 This has 2 variations one in OfsY to give a movement from screen right to left, and one in the OfsZ to give some dynamic motion to the foam. OfsY, at frame 1 and at frame 250. OfsZ, at frame 1 and at frame 250. Page 38 of 41 Created by Colin Litster April 2004

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40 Tiny Waves ~ Texture slot 4 This just has an OfsZ variation. OfsZ, at frame 1 and at frame 250. Page 40 of 41 Created by Colin Litster April 2004

41 SAVE YOUR WORK OK that s all the material and textures set up. Time to render an animation. I would suggest a small test render of about 320x180 with no OSA or MBLUR, but do use the unified renderer. Render to an AVI RAW file and PLAY the result. You may have to create some extra lights to show the far ocean, or some nice lightning flashes will do the same thing. Those are created with a light IPO in a similar way to object and material IPOs. You can also animate some movement in the camera as though it were on the sea. Have a go at altering the material colour to Blue and try the same animation. Happy Blending and don t get seasick COG Page 41 of 41 Created by Colin Litster April 2004