Resizing images

[JoshDB]

Hey all. So far I've displayed and centered images in my image viewer using this -

Code: Select all

function ImageViewer(loc)
	tempimage = Image.load(loc)
	if tempimage&#58;width&#40;&#41; > 480 and tempimage&#58;height&#40;&#41; < 258 then
		minusc = tempimage&#58;width&#40;&#41; - 480
	elseif tempimage&#58;height&#40;&#41; > 272 and tempimage&#58;width&#40;&#41; < 481 then
		minusc = tempimage&#58;height&#40;&#41; - 258
	elseif tempimage&#58;width&#40;&#41; > 480 and tempimage&#58;height&#40;&#41; > 258 then
		if tempimage&#58;width&#40;&#41; > tempimage&#58;height&#40;&#41; then
			minusc = tempimage&#58;width&#40;&#41; - 480
		else
			minusc = tempimage&#58;height&#40;&#41; - 258
		end
	end
	if minusc == nil then
		tempcentx = tempimage&#58;width&#40;&#41;/2
		tempcenty = tempimage&#58;height&#40;&#41;/2
	else
		tempcentx = tempimage&#58;width&#40;&#41; - minusc
		tempcenty = tempimage&#58;height&#40;&#41; - minusc
		tempcentx = tempcentx/2
		tempcenty = tempcenty/2
	end
	centerx = 480/2 - tempcentx
		
	centery = 258/2 - tempcenty
	minusc = 0
	while true do
		screen&#58;clear&#40;&#41;
		screen&#58;blit&#40;0,0,white&#41;
		screen&#58;blit&#40;centerx,centery,tempimage,0,0,tempimage&#58;width&#40;&#41; - minusc,tempimage&#58;height&#40;&#41; - minusc&#41;
		screen&#58;blit&#40;0,0,ivt&#41;
		button = Controls.read&#40;&#41;
		if button&#58;cross&#40;&#41; then
			screen.waitVblankStart&#40;10&#41;
			break
			screen.waitVblankStart&#40;1&#41;
		end
		screen.flip&#40;&#41;
	end
	screen.flip&#40;&#41;
end

I thought screen:blit(centerx,centery,tempimage,0,0,tempimage:width() - minusc,tempimage:height() - minusc) would also resize the image, but no. It just displays certain portions of the image, and the rest is cut off.

Is there some way to do this?

[Durante]

Sure, use screen.blitScaled() in my version :P

But seriously, there's no scaling in standard LuaPlayer as of now that I know of. It would also be really slow if you do it in software.

[JoshDB]

I found something kinda helped me.

Code: Select all

function Image:magnify(mag) 
  mag = mag or 2           -- 2 times in size by default 
  local w = self:width()  
  local h = self:height() 
  local result = Image.createEmpty(mag*w, mag*h) 
  for x = 0, w-1 do 
    for y = 0, h-1 do 
      result:fillRect(mag*x, mag*y, mag,mag, self:pixel(x,y)) 
    end 
  end 
  return result 
end 

But it resize by a fraction, and I haven't tested to see if it works for small fractions like 0.5.

Thanks in advance for any help.

[KawaGeo]

I modified the code you posted above. It does not do some fraction. Only double, triple, etc. of a given image. Sorry.

Perhaps, the new version 0.12 would do the trick. I haven't taken a look into it, yet.