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 ahso 12-04-2011 03:04 PM

nested for/while loops

Hi
a function returns Z (height) after giving X and Y location. How
would those two for (or while?) loops look like if I need all z points
in a rectangle.
Many thanks
Michael

 ralph 12-04-2011 04:32 PM

Re: nested for/while loops

On Sun, 4 Dec 2011 07:04:41 -0800 (PST), ahso <ahso47@yahoo.com>
wrote:

>Hi
> a function returns Z (height) after giving X and Y location. How
>would those two for (or while?) loops look like if I need all z points
>in a rectangle.
>Many thanks
>Michael

I'm probably missing something as that question doesn't make any
sense.

Even assuming each "X" and "Y" describes a point. Everything else
would be simple linear addition or substraction.

-ralph

 Nick Keighley 12-04-2011 05:23 PM

Re: nested for/while loops

On Dec 4, 3:04*pm, ahso <ahs...@yahoo.com> wrote:
> Hi
> *a function returns Z (height) after giving X and Y location. How
> would those two for (or while?) loops look like if I need all z points
> in a rectangle.
> Many thanks
> Michael

you need to work out how X,Y gets turned into Z

 Victor Bazarov 12-04-2011 05:41 PM

Re: nested for/while loops

On 12/4/2011 12:23 PM, Nick Keighley wrote:
> On Dec 4, 3:04 pm, ahso<ahs...@yahoo.com> wrote:
>> Hi
>> a function returns Z (height) after giving X and Y location. How
>> would those two for (or while?) loops look like if I need all z points
>> in a rectangle.
>> Many thanks
>> Michael

>
> you need to work out how X,Y gets turned into Z

No, [s]he needs to work out how "a rectangle" turns into X and Y.

V
--

 ahso 12-05-2011 06:56 AM

Re: nested for/while loops

Ok it's a little more complicated:
---
Probes the terrain. Pass in the XYZ coordinate of the probe point...
Other fields are filled in if we hit terrain, and a probe result
* is returned.
----
So i give that function x,y,z coordinates and if it hits terrain I get
a result. Now I see why i only get a few points to draw as it hits
around the viewer but loses ground contact in the mountains etc.
I want to get the z (ground contact) within a 128x128 square around my
position, for a heightmap. (color z in different colors)
Many thanks indeed as I'm stuck...
Regards Michael

 Werner 12-05-2011 10:13 AM

Re: nested for/while loops

On Dec 5, 8:56*am, ahso <ahs...@yahoo.com> wrote:

> Many thanks indeed as I'm stuck...
> Regards Michael

Post some code...

 ahso 12-05-2011 02:19 PM

Re: nested for/while loops

Getting closer, now I have lines from top left to bottom right:

for( int x=0; x< 16384; x++ ){
draw x,y,z

I need also a y for loop?
Thanks
Michael

 Victor Bazarov 12-05-2011 04:59 PM

Re: nested for/while loops

On 12/5/2011 9:19 AM, ahso wrote:
> Getting closer, now I have lines from top left to bottom right:
>
> for( int x=0; x< 16384; x++ ){
> draw x,y,z
>
> I need also a y for loop?
> Thanks
> Michael

Michael,

You need to sit down and write your algorithm with a pencil on a piece
of paper. "I have lines from top left to bottom right" - what does that
mean? We have no idea. It's not a description of an algorithm.
Perhaps you need to think about the algorithm for a while. Perhaps you
should also look into some *formality* in your activities. So far your
posts indicate that your work is very hap-hazard. Step back from
programming for an hour and think what actions you would take if you
were the computer and you needed to accomplish whatever goal you're
setting for it.

To make tea, what do you need? You need a cup, water source, dry tea
(loose or in a bag) and a way to heat the water to the boiling point.
Water source is in the kitchen (or the bathroom). So, as part of the
algorithm for making tea you need to ensure you're in one of those
locations. To boil water you need some energy source. A microwave
would do (make sure it's plugged into an electrical outlet). And so on.
You write down preconditions, then you write down your actions. It
becomes the algorithm for accomplishing your goal.

Same thing with making calculations. Or drawing a shape. Or
controlling a nuclear reactor. You need the algorithm first, THEN you
can put it in terms of the language you've chosen to implement it.

V
--

 ahso 12-06-2011 07:07 AM

Re: nested for/while loops

 Ian Collins 12-06-2011 07:15 AM

Re: nested for/while loops

On 12/ 6/11 08:07 PM, ahso wrote: