World: r3wp
[gfx math] Graphics or geometry related math discussion
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Chris 19-Aug-2007 [36x2] | I wrote this before HSV functions were added to /View, but it still works: http://www.ross-gill.com/r/hsv-lab.r |
But now there are native hsv functions... | |
Robert 20-Aug-2007 [38x2] | This is my colour palette: ; 7 primary colors bn-green: 0.102.76 green-field: 51.133.110 reed-green: 102.163.146 patina-green: 153.194.183 glass-green: 204.224.219 light-green: 232.241.239 ash-gray: 209.209.209 ; 7 secondary colors midnight: 0.29.43 foggy-morning: 31.93.154 hazy-day: 102.154.204 light-mint: 154.204.205 terra-cotta: 205.153.103 desert-sand: 229.201.115 sunflower: 254.191.0 |
It's stated that this palette is specialy designed to harmonize. And I want to get a palette being based on blue with the same properties. | |
Rebolek 20-Aug-2007 [40] | REBOL [] colors: [ ; 7 primary colors bn-green 0.102.76 green-field 51.133.110 reed-green 102.163.146 patina-green 153.194.183 glass-green 204.224.219 light-green 232.241.239 ash-gray 209.209.209 ; 7 secondary colors midnight 0.29.43 foggy-morning 31.93.154 hazy-day 102.154.204 light-mint 154.204.205 terra-cotta 205.153.103 desert-sand 229.201.115 sunflower 254.191.0 ] change-colors: func [val /local h hsv][ forskip colors 2 [ hsv: rgb-to-hsv colors/2 h: hsv/1 + val // 255 hsv/1: h colors/2: hsv-to-rgb hsv ] ~b1/color: colors/bn-green ~b2/color: colors/green-field ~b3/color: colors/reed-green ~b4/color: colors/patina-green ~b5/color: colors/glass-green ~b6/color: colors/light-green ~b7/color: colors/ash-gray ~b11/color: colors/midnight ~b12/color: colors/foggy-morning ~b13/color: colors/hazy-day ~b14/color: colors/light-mint ~b15/color: colors/terra-cotta ~b16/color: colors/desert-sand ~b17/color: colors/sunflower ] lay: layout [ across ~b1: box colors/bn-green ~b2: box colors/green-field ~b3: box colors/reed-green ~b4: box colors/patina-green ~b5: box colors/glass-green ~b6: box colors/light-green ~b7: box colors/ash-gray return ~b11: box colors/midnight ~b12: box colors/foggy-morning ~b13: box colors/hazy-day ~b14: box colors/light-mint ~b15: box colors/terra-cotta ~b16: box colors/desert-sand ~b17: box colors/sunflower return button "change color" [change-colors 64 show lay] ] view lay |
Robert 20-Aug-2007 [41x2] | Thx a lot!! :-) |
I will play around with this. | |
Rebolek 20-Aug-2007 [43] | you're welcome :) |
Geomol 9-May-2008 [44x2] | Has anyone got experience with this Texturing Tool? http://www.mapzoneeditor.com/index.php |
Or know of a good place to look for texture producing algorithms? | |
Reichart 11-Jul-2008 [46] | Look towards people in the video game business....they did lots of this in the 80-90s |
Rebolek 11-Jul-2008 [47x3] | http://www.rebol.org/cgi-bin/cgiwrap/rebol/view-script.r?script=texture-lab.r |
It's nothing special, but it works :) | |
press "Open" to see some presets | |
Anton 7-Jan-2009 [50] | Hi, I'm looking for a range of colours from "hot white" to "cool blue" to represent molten metal cooling down. Currently I have this range of 6 colours: colors: [white yellow orange red purple navy] (I interpolate between the colours for more resolution.) Does anybody know how I can improve these colours ? Any websites that are good for this? |
Tomc 8-Jan-2009 [51x2] | I made a RGB<->HSV back in the dawn of time I think newer rebols have it built in |
using HSV it is trivial to divide your start and end points into as many steps as you need | |
Henrik 8-Jan-2009 [53] | R3 has some RGB<>HSV<>HSB code as mezzanine. Perhaps it can be backported to R2. |
Chris 8-Jan-2009 [54x3] | 'hsv-to-rgb and 'rgb-to-hsv are in 2.7.6 |
I have a white-to-color function 'make-wash-table here. Principle would be similar, I guess... | |
http://ross-gill.com/r/arrow-style.r | |
Anton 9-Jan-2009 [57] | Thanks guys, I know about the hsv-rgb conversion functions, and the interpolation can be improved using them, but I really wanted to improve the colours specified in the COLORS block. That means I'm looking for palettes of ~6 colours which aim to define a colour range like that of cooling metal "in the real world". But never mind, while it looks really cool to use a range of 6 colours, I'm now more of the opinion that it confuses the user interface too much - so I've now using a simple 2-colour range ! Thanks Chris for a look at your code. |
Gabriele 10-Jan-2009 [58] | Anton, isn't the H in HSV what you wanted indeed? The actual real life colors... |
Anton 10-Jan-2009 [59] | .. of course - Hue helps. I was sort of hoping for a palette that was maybe generated from scientific data, or an artistic eye. I was hoping to locate a website with palettes for different metals etc. Someone out there must be doing it. Just trying to locate such information is difficult because coming up with specific enough search keywords is hard in the sea of information about colour. But never mind, never mind, I can do it myself - I think it's faster :) |
jocko 10-Jan-2009 [60] | Why not use the Matlab palettes. They are matrices of 256 colors ( RGB values), with different themes (spectrum, fire, jet, autumn, copper). You could retain only a small subset of them. |
Anton 10-Jan-2009 [61] | Aha, that gives me a lead to follow, thanks jocko. |
Gabriele 11-Jan-2009 [62] | My point is that "hue" is that "scientific data", that is, light wavelength. artistic eye is a different matter though. |
Anton 11-Jan-2009 [63] | No, just grading hue by itself is not enough to qualify as "scientific data" for me :) You understand that different materials have different colours at different temperatures. As gold and steel cool down from hot white, they must pass through various colours and brightnesses before returning to their normal room temperature colours. This "cooling colour signature" varies from material to material, obviously. That's what I meant. But anyway, I'm likely to get further using my "artistic eye" than searching for such data. |
Gabriele 12-Jan-2009 [64x2] | I'm not entirely sure about that. The emitted light wavelength depends on the temperature only on first approximation. the "room temperature color" is reflected light, which has nothing to do with the emitted light. Of course there are other variables, but I don't see them significant in this case. |
What different materials differ on would be which wavelength they absorb, while emitting. (and clearly reflection has a part in that), but for metal I'd guess that most of the light you see is coming from the surface. I don't think these things are significant enough for your purposes, but maybe they are, i'd need to check. doesn't Wikipedia have this stuff? | |
Anton 12-Jan-2009 [66x2] | I don't know, I haven't had time to check Wikipedia thoroughly. But as we consider it more closely, we can see many factors contribute to the final colours. |
I don't think I mentioned what I wanted the colours for - a progress bar. After consideration, I've pretty much decided that a large range of colours such as cooling metal might go through might actually be bad for the user interface (unless extreme measures are taken to make it really look like molten metal, like a computer game programmer might do), because all those colours might be confusing, and some of them (eg. red) may signal warning, etc. (especially if the user hasn't seen the progress bar before - I don't want to present the user with a circus of colours). Fading from white to solid blue is what I'm using at the moment, and I'm thinking white might be too bright. | |
Reichart 12-Jan-2009 [68x2] | May I suggest that: - Starting with just cold metal - metal is not a single colour. You are seeing many colours at all times, and different patches of colour everywhere. You are seeing colours reflected and you need a coefficient table to calculate the reflection index. Copper for example would lean heavily towards red. - Next, heated metals are the same, meaning, not a single colour either, but now for a different reason. But to produce the illusion of something burning hotter and hotter will require something that is multi-pass, and changing constantly. In video games to produce the afterburner on a jet we did a few tricks: - The jet flame itself was made of a cone-like shape (maybe a dozen polygons). - The cone was set with an alpha channel so that the source was close to opaque, and the tip was close to translucent. - A second cone was placed around the first cone, but just slightly larger. - They both undulated at all times. In other words, the length was always changing for both cones independently just slight. And when the jet went faster and slower, they changed from long to flat (with the plane itself). - The textures on the polygons were already a rainbox of colours, but as the jet changed what it was doing, the colour pallet was changed. Again, both cones were not always changed at the exact same time. - Just behind the jet (but depending on your angle of view), several filters (polygons that read the bg info and render again) would be used to create a small waiver and a refocusing. The more GPU you had, the more of this you could do, and the better the final effect would look. - Lastly, and this is what makes the whole thing amazing in a 3D game. We are always checking the location of bright things, such as the sun, or things like the after burner filling your screen. If so, we change the contrast of the whole world, and flare out your iris. In the case of the sun we throw up a lens flare, and darken all the ships in the sky. Even as a 2D problem, you should attach this the same way. This video I think drives this all home for you. http://www.youtube.com/watch?v=mHL94qQgl_8&feature=related |
This photo drives this point perfectly http://www.richard-seaman.com/Aircraft/AirShows/Nellis2006/Extras/BelgianF16Afterburner.jpg See how the jets are making the left wing blurry...this is what makes it look hot more than even seeing the jet itself. That just tells you the source, not that it is so hot it messes up the air. | |
Maxim 12-Jan-2009 [70x4] | also don't forget that light is additive, so sometimes, all you need to do, in visual effects, is add up an immense number of very dark particles. where they are tightly packed, it will create a ball of white, by iteself. |
the different hues, will build themselves up based on the falloff your particles are spreading out at. | |
the same probably applies wrt the way the color spreads out over the time it cools down and/or the distance from a single hot point. | |
if your base color is some kind of darkish brown, it will glow from brown to orange to yellow to white. the bluish tint usually comes from the surface which "blues" because its exposed to heat. not all metals "blue". some melt before getting that hot. | |
Anton 13-Jan-2009 [74x3] | Wow - you guys. This is very interesting, but, going too far for my purpose at the moment. I *really* like the idea of having the simplest, most robust code possible. Adding so many visual effects and detail is something for a computer game. |
I'm mostly concerned with communicating as simply and directly as possible to the user the current overall progress of some operation (multiple file download is first application). | |
(I appreciate all the technical details very much, however.) | |
Oldes 13-Jan-2009 [77] | This site is good for color picks http://www.colourlovers.com/ |
Henrik 13-Jan-2009 [78] | nice one, Oldes. |
Robert 13-Jan-2009 [79] | Yes, cool. |
Brock 13-Jan-2009 [80] | Interesting stats in the lower right corner of the page... About Colourlovers. An idea of what we could have for the AltME stats on Rebol.org as suggested in another group. |
Anton 14-Jan-2009 [81] | *That*'s the kind of website I was after, thanks Oldes. |
Maxim 28-Jan-2010 [82] | anyone know if/where I can find an implemented shortest path algorythm in rebol? I know I can do my own... but if one exists and available, I'd rather use it :-) |
Cyphre 29-Jan-2010 [83] | Maxim, do http://cyphre.mysteria.cz/a-star.r that is my very old script I used for prototyping when developing strategy games couple of years ago. It's not optimized as it is just prototype before conversion to Java but it kinda works ;) |
Gabriele 23-Feb-2010 [84] | http://www.4p8.com/eric.brasseur/gamma.html |
Gregg 23-Feb-2010 [85] | Thanks for posting that Gabriele. I had no idea. |
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