I second this. We neeeds it.

Kay, I figured it out.

I would have posted this much earlier after lunch, but I had work and my wireless network was down.

Here are some perfect and useful workarounds.

int GetMapPixelWidth()	//Get the width in pixels of the map..


{


int done = 1;		//When we're done...


			//Set the variables to come back to...


int prevxwin=xwin, prevcam = cameratracking;


int lastxwin;		//Keep track of Xwin...


lastxwin--;


xwin = 0;		//Start xwin.


cameratracking = 0;	//Manual cameratracking.


while (done)


	{


	xwin++;


			//If xwin goes past the edge of the map, it will stop


			//increasing.  We use this final value,


			//together with the screen resolution,


			//for the width of the map.


	if (xwin == lastxwin)


		{


		done = 0;


		}


	lastxwin = xwin;


	//Log(str(xwin));


	Render();


			//Not calling ShowPage()...speeds it up.


	//ShowPage();


	}


xwin = prevxwin;	//Reset variables.


cameratracking = prevcam;


			//Return pixel width of map.  Add the screen size,


			//because xwin stops increasing when there


			//is still a whole screen of real-estate left


			//before the map ends.


return lastxwin + ImageWidth(screen);


}





int GetMapPixelHeight()	//Get the height in pixels of the map.


{


int done = 1;


int prevywin=ywin, prevcam = cameratracking;


int lastywin;


lastywin--;


ywin = 0;


cameratracking = 0;


while (done)


	{


	ywin++;


			//This runs on the same principle as


			//GetMapPixelWidth().  After increasing


			//to the edge of the map, ywin will


			//stop increasing.  Get the final value.


	if (ywin == lastywin)


		{


		done = 0;


		}


	lastywin = ywin;


	//Log(str(ywin));


	Render();


	//ShowPage();


	}


ywin = prevywin;


cameratracking = prevcam;


			//Return the final ywin position


			//plus the screen height to make up


			//for the last screen of the map.


return lastywin + ImageHeight(screen);


}

They work well.

Omni,
that is a nifty function. How did you figured out that xwin/ywin will stop increasing at the end of a map?

Omni,
another question:
is there a reason why you use xwin++ and ywin++?
I tried xwin += 16 and ywin += 16 and it seems like it works too (and much faster). As long as the tilesize is hardcoded to 16x16 this should work.
Or is there a obvious reason for single incrementation I'm to stupid to see?

I figured out how xwin and ywin behaved when I was working on my older map scaling/rotation library for V2...and to do that I needed to learn to translate xwin/ywin to the screen and position map layers. In doing so I realized that:

1. Xwin and Ywin start at 0, the upper left corner of the map.
2. Xwin and Ywin do not increment when under player control until the player reaches the center of the screen (in 320 width screen, a 160 area).
3. Xwin and Ywin stop decreasing when the lower right hand corner of the map is in the lower right hand corner of the screen. So they stop decreasing not at mapwidth, mapheight, but at mapwidth-screenwidth, mapheight-screenheight.

The reason why I only use xwin++ and ywin++ is because...well, actually, I did use xwin+=10 etc...on my machine when I was first testing it. But this caused the final width to be off by 10 pixels.

The reason is because xwin and ywin stop incrementing when they reach the edge of the map...and when I increased it by 10, my logs originally didn't show it being truncated, since I logged before Rendering(). It was the original width+10.

So I just used 1, since there's no speed barrier.

But according to Kildorf's post, Render() does indeed truncate the values. Good. Kildorf's is good :)

Quote:Originally posted by Blues Zodiakos

If you need it, there are two small functions in my particle system demo that convert x and y map coordinates to screen coordinates, and two functions to determine if the map coordinates you give it are within the viewing area (both are resolution independent, I believe). It's really simple code, don't remember how fast it is though. Just thought I'd say something. :D

I have something similar in the code for something I'm working on that takes the mouse co-ordinates and can tell you what TileXY the mouse is hovered over etc.

Quote:Originally posted by overkill

Map to screen is easy:

RectFill(map_locx-xwin,map_locy-ywin,map_locx-xwin+16,map_locy-ywin+16,RGB($33,$66,$FF),screen);

Yeah.



Er, sorry to have to ask, but what exactly does that DO?