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Text File | 1991-06-06 | 19KB | 604 lines

December 1990 BRUSH_4D v. 1.2 ---------------- Files: Brush_4D Program. This doc file. Help picture. Copyright © 1990 by Bruce Thomson S H A R E W A R E Brush_4D is ShareWare. No guarantee is made, expressed or implied as to Brush_4D's suitability for any application. No responsibility will be taken by the author for any results of its use or misuse. This is Shareware. It is not the best version of this program available. For most people this version will be more than adequate. It coverts brushes with a maximum of 200 x 200 pixels and will create objects with a maximum of 2000 faces. It has all the features of the larger version except for this size restriction. If you use this program then please send $US10 to the address below. If you want the unrestricted version send $US30 to register. If you think you might want the unrestricted version at a later date send $10 now and $20 later. Registered users will be sent updates. 1. What Does It Do? Brush_4D converts IFF brushes (e.g. DPaint pictures) into Sculpt objects. The program will convert standard brushes, Extra Halfbrite brushes and HAM brushes in full colour. It is quite fast. In addition to converting your brush into a flat object, pixel for pixel Brush_4D has some extra features. - Optimise the brush so that areas of the same colour become one large square as opposed to many small ones. - Make any colours transparent. - Wrap brush around a tube or part of tube. - Wrap brush onto a sphere. - Wrap brush with some special effects. - Each colour of the brush can be of a different texture. - With HAM images allow extra optimisation through a HAM colour closeness setting. 2. How Do I Use It? Brush_4D runs from CLI or Workbench and is easy to use. It needs about 110K of free memory as well as the screen memory for your picture. When running respond to the requesters in turn and the object file will be created to load into Sculpt 4D as an object or scene. You will need a copy of 'req.library' in your LIBS: directory. 3. How Does It Work? Brush_4D loads in the brush as a picture and displays it on its own screen. Specify the type of conversion required and any extra parameters. Based on your input any colours you have specified to be transparent (and thus not converted as part of the object) will be blocked out on the picture. Brush_4D will then proceed to analyse the picture and convert the pixels into pairs of sculpt faces making up squares with that block's colour. If the optimise option has been selected rectangular areas of the same colour will be converted into one large block as opposed to many individual pixels of the same colour. Depending on the brush, optimisation of up to around 90% can be achieved, giving a great saving in memory and object faces. When the whole brush has been converted the points will be wrapped around the selected shape if one has been chosen. The data will be written out, ready to be loaded into Sculpt Animate/4D/3D etc. as an object. You will be told of the number of vertices, edges, faces and file size of the object, along with the percentage of points made transparent and the percentage of compression performed. 4. Wraps. Apart from just converting your brush into a flat, 2D rectangular plane Brush_4D can wrap your image onto certain 3D shapes. These are a tube, a sphere and various sinusoidal waves. For example you can wrap a picture of a face onto a sphere to get a reasonable 3D head. The sphere and sine wave are based on the wrap to tube. With wrap to tube you get an upright tube with the X values of the pixels wrapped around a circle and the Y values making up the height of the tube. Spheres are made by adjusting the diameter of the tube at each height level so that it is squashed in at the top and bottom and stretched out in the middle. Sine waves are made by modifying the diameter of the tube to match a sine wave with several parameters (see below). 5. The Inputs. A series of requesters will pop up which you will use to specify the conversion type and specifications. For each click on the preferred alternative or enter a value in the range offered. First you must select the filename for the IFF brush. "Wrap type Flat or Wrapped" Flat - The picture will be converted to a flat, 2D object. Wrap - Choose one of the below wrap types. "Wrap type Tube Sphere or Sine" Tube - The picture will be wrapped around a tube. You will be prompted for two responses at this point. "Bend level for tube ..." Enter a number in the range 0 to 1. This will be the proportion of a circle that is turned through. 0 will make a flat object. 1 will wrap completely around a tube. 0.5 will wrap to a half tube. See help picture. "Bend forwards or backwards..." You should decide whether the picture will be curled around the tube clockwise (backwards) or anticlockwise (forwards). Forwards is normally used, to preserve correct orientation. See help picture. Sphere - You will be prompted for the values as in the Tube option. Wrap to sphere works by wrapping to a tube and then altering the diameter of the tube at each point to match a sphere. By doing this the picture will look a little squashed towards the top and bottom of the sphere. Sine - You need to enter the values for wrap to tube and then you will be asked for start and end angles for the sine wave. These values are in degrees. Wrapping to sine works by running a wriggle down the side of the points mapped to a tube so you can get effects like the look of the old style Coke drink bottles. The start and end angles give the range of values through which your wriggle will run as it travels down the side of the tube. You will then be asked for "radius offset". This will control how pronounced the wriggle is. Values range from 0 upwards. A value of 1 is equal to the amplitude of the sine wave and higher values will increase the diameter of the tube prior to adding the wave thereby lessening the effect of the sine wave. A value of zero will give shapes like an hour glass that converge in the middle. See help picture. If you have chosen any of the wrap options you will be given the option to select how the wrapping will be done. If you select "Ignore transparent..." as YES then the wrap will start at the top left corner and proceed to the height and width values you will enter below. If you say NO then the wrap will be based on only non- transparent colours in the brush. With this option you can choose a tight wrap or a loose wrap. It can also be used to ensure equal curvature can be given to brushes with unequal widths, and to avoid some of the squashing and stretching of a wrap to sphere. "Optimise x pixels..." and "Optimise y pixels..." If you select optimised for either then rectangles of one colour will be found and converted to one large block. This is fine for flat objects. However this could cause a problem with the wraps, though, as very large areas being optimized would cut across the middle of their shape. This can be avoided by entering suitable values for the maximum block size. "X direction" and "Y direction" will specify the maximum number of pixels that can be used in one block. You will not be prompted for these when you are creating a flat object as they would serve no purpose. If you are going to wrap to a tube then it would be best to set the maximum X optimisation, depending on total brush width to perhaps 5 pixels. In this way it retains a reasonably circular shape. If you want a smoother circle then use a smaller maximum X direction blocking. The level by which you optimise Y depends on the wrap. With a tube you should optimise completely by entering a value in excess of the height of the brush. If you are wrapping to a sphere or sine then the same considerations as for X optimising apply. e.g. To make a simple 3D globe you will want to wrap a flat map onto a sphere. If your brush was 100 * 60 pixels then you might use 4 and 3 for the maximum optimisation levels. In this way you would benefit from optimising areas of one colour but not to the extent that large areas such as USSR were flat and no longer looked spherical. Your map would have at a minimum 25 segments forming a circle around the equator. You may not want to convert the whole of the brush. You have the option of using only a portion of the brush measured from the top left corner of the picture. On "Width" and "Height" the default values are the dimensions of the brush. If you want something smaller enter that instead. In the restricted size version of Brush_4D you will have a maximum area that can be converted. If your entered values are less than the maximum then a border will be drawn around the area you have selected so you can see just what you have taken. If you would like different colours to be different textures in the object then respond "yes" to "Change Textures?" All colours start off as being dull. Enter ranges of colours for which you wish to change the texture. Click on the texture of choice from the gadgets. All colours in the range will become this texture. If you want to alter only a single colour use a single number for start and end of the range. "Cancel" the requester to finish entering ranges. Note: This is for non-HAM pictures only. With EHB the half-brite colours must be textured separately from their corresponding bright colours. You are now prompted for any colours that you would like to make transparent. If you have a HAM screen you have only the option of making palette colour 0 transparent. This is usually the background colour. If the picture is a non-HAM picture then you will be asked for a list of colours you want to be made transparent. These numbers correspond to the palette colour in the picture. When you have finished entering colours to be made transparent click on "Cancel." The picture will then be scanned and pixels that are to be transparent will be coloured in on non-HAM displays. On HAM displays the background colour will be made transparent but not shown on screen. You will be shown what proportion of the pixels in the brush were made transparent. With HAM pictures you will be able to enter a value that allows colours that are close to each other to be treated as the same colour. This gives extra optimisation as you get more large blocks of one colour rather than say two different blocks of almost the same colour. At the prompt "Enter HAM Threshhold..." enter a value of 0 to 15. Each pixel has a red, green and blue component and your entry is the level that they are allowed to vary from the surrounding pixels before they are considered to be a different colour. A value of 0 means any difference at all between pixel colours will be detected. A value of 5 will allow for example any colours between dull orange and medium orange to be treated as one colour. A value of 15 will make the program think that all the colours are the same. Higher values result in less detailed colouring of the object but fewer faces. 6. While it Runs. Once you have entered these values sit back and depending on the size of the brush up to a minute later the conversion will be done. The graphic screen that Brush_4d works on is behind its selection screen. You can drag down its screen to watch it in progress. As the picture is processed, in non-HAM screens the points converted will be blocked out as it goes. In HAM screens because writing to the screen would change the colours and mess it up you can get an idea of where it is up to by choosing a new height value of a couple of pixels less than the maximum and you will see a line run across the bottom. When all the processing is done you will be shown the exact number of vertices, edges and faces used in the object and the file size. You will also be told the level of compression of the non- transparent colours if you had any optimisation on. Now enter the filename that you would like the object saved under. If you decide that you don't want this object after all then click on 'Forget it' or the close gadget and then 'Abort'. 7. Tips. Don't click the hidden forward/back gadgets on the graphic screen as they leave an outline that may turn up in your object. Fewer colours will result in higher compression levels but you should balance the memory saving against the look of the object. If you want smaller objects then reduce the brush before conversion or reduce the number of colours on a program like Deluxe Photolab. Name your objects when they are loaded in as when you have transparent colours the various parts may not be connected so you will want an easy way of selecting the whole object. When wrapping to a sphere you can get quite a bit of distortion at the top and bottom. This can be controlled by using the "Ignore Transparent for Bend" setting on NO. On your paint program cut your brush, clear the screen, and stamp the brush in the middle of the screen. Then cut the brush with a large border above and below which can be made transparent. The transparent colours will not show up as part of your object but will be included in calculation for how much to bend the tube. With this you will not get a sphere but more of a sphere with the top and bottom cut off. This can be a good effect. The same works for sine wave but there is not often the same level of distortion with this. Use the HAM threshhold setting around 2 or 3 for good looking results with increased optimisation. If you want more than the 64 colours in EHB and don't like the fringing associated with HAM colours (which will be faithfully converted over) then you can go to a little trouble and create your objects in parts. These can be quite easy to assemble. Using DPaint - Draw your brush using all available colours. Use the coordinates and cut it out and save it. Change the palette and by using Stencil (in Dpaint) select the background colour, invert the stencil then return to painting. Use one colour to paint over the pixels in the old brush. Then change the stencil so that colour is protected and the background colour free. Draw around the old picture with your new colours and when you have finished go back to stencil and protect everything but the colour you used to write over the first pictures pixels. Now rub over them with the background colour. Turn off the stencil. Now cut the new brush with exactly the same size and start point and save. Convert both into objects and layer one over the other (they should start that way when you load them in as scenes). As well as just converting everyday brushes into objects you can use Brush_4D as a simple object creator. One use I find for it is as a replacement for the checkered floor. Make your own checkered floor with something like a pattern fill and then convert it. You now have control over the size of your GROUND and can have more than two colours and don't have to place it horizontally at level 0. It can also have a texture. Have more than one ground. For stripey tubes make a row of colours with something like the shaded fill in DPaint and wrap it to a tube. Convert your favourite (colour) fonts over. Make them 3D by wrapping them around part of a tube, both forwards and backwards bent and put together - no longer flat and boring. Do nice keyframe animations with pictures fading into one another, sine waves squirming as you alter the start and end angles etc. - just make sure you don't optimise and have no transparents and have exactly the same size in your start and end brushes. 8. Errors. You will be told throughout if anything goes wrong like not being able to open the screen or files etc. You might get the "Exceeded maximum vertices" or "Exceeded maximum faces" message. If this happens you should send off the cash for the version without limits. Alternatively reduce your image (but lose detail). If you run the programs but it returns immediately then you may not have the "mathtrans.library" or "req.library" in your LIBS: directory. Check your stack size as well. 9. The Competition. DigiWorks 3D ($US 130-160) - I see it as a complementary product as it does only flat conversions (extrusions don't really count) and doesn't handle colour at all. It is nice though in finding edges etc. for you. With my program you will get "jaggies" on diagonal edges, with DigiWorks you would get one diagonal line. Living out of the way I haven't seen anything else which performs similarly. Perhaps you would like to send me some :-) 10. The Address! I am a poor student, and need your donations to buy 'Imagine'. Future upgrades depend on your generosity. These will be sent free of charge when any important changes are made, to all registered users. Send your money to: Bruce Thomson PO Box 33116 Takapuna Auckland NEW ZEALAND Make that $US cash or international cheques or money orders etc. If you're in a kindly mood send all you've got, copies of any other shareware/PD ray tracing utilities, comments, suggestions etc $NZ acceptable also. Use current exchange rate. 11. Other Important Stuff. This program is to be distributed with these docs intact and unaltered. The help picture is to accompany it. Distribution of restricted version. (ie this package) - This restricted version is freely uploadable to BBS's etc. - Fred Fish can include it in his library. - Other PD/Shareware libraries can distribute it if they are not greedy, ie they charge no more than 150% of Fred Fish's charges. - Free User Group disk magazines, etc. may distribute it. - Ask me if you want to distribute it packaged in any form that is not covered above, that you will be charging any money for - e.g. a disk that accompanies a magazine The unrestricted version is for your private use only if you decide to register. It is not to be copied.