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The paint method for this class begins by setting up a pair of nested for loops that will be used to process each elevation point on the surface, and by initializing the color values for red, green, andblue to 0 in the innermost loop.

Set white and black for max and min values

If the elevation value is equal to 255, color values are set to cause that elevation to be painted white. If the elevation value is equal to 0, color values are set to cause that elevation to be painted black.

Listing 23 sets the color values to cause the extreme values of 0 and 255 to be painted black and white. Note that the code in Listing 23 is the beginning of a series of if-else constructs.

Listing 23. Set white and black for max and min values.
if((int)data[row][col]== 255){ red = green = blue = 255;//white}else if((int)data[row][col]== 0 ){ red = green = blue = 0;//black

Elevations other than the extreme ends

If the elevation is not one of the extreme values of 0 or 255, control passes to code that subdivides the total elevation range from 1 to 254 into thefollowing four ranges and then sets the color values for each range separately:

  • 0 less than elevation less than or equal 63
  • 63 less than elevation less than or equal 127
  • 127 less than elevation less than or equal 191
  • 191 less than elevation less than or equal 254

Processing the lowest range

Listing 24 shows the code that is used to process the lowest range of elevations between 1 and 63.

Listing 24. Process elevations from 1 to 63 inclusive.
}else if(((int)data[row][col]>0)&&((int)data[row][col]<= 63)){ int temp = 4 * ((int)data[row][col]- 0); blue = 255;green = temp;

What we are shooting for here is to produce color values that will result in a smooth gradient of color from blue at the low end to aqua at the high end ofthe range.

(See the leftmost one-fourth of the calibration scale for the middle image in Figure 1 .)

Scale the elevation values

Listing 24 begins by multiplying the elevation value by a factor of 4 to put it into the range from 4 to 252. This makes the elevation values compatible withallowable color values that range from 0 to 255.

The color aqua

The color aqua is produced by mixing equal amounts of blue and green. Listing 24 holds the value of blue constant at 255 and increases the value of green in proportion to the elevation value. Thus, at the lower end of the range, blue hasa value of 255 and green has a value of 4. (This is almost pure blue.) At the upper end of the range, blue still has a value of 255 and green has avalue of 252. (This is almost the pure secondary color aqua.)

In all cases, the value of red is 0 within this range. These color values (blue and temp) will be used later to instantiate a Color object, which will be used to control the plotting color for that portion of thedisplay.

Processing the other three ranges

Now that you know the basic scheme, you shouldn't have any difficulty understanding the code for processing the other three ranges shown in Listing 25 .

Questions & Answers

do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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