get the position where i click on a map

[tommymaster]

Hi! I draw a map on a player's screen, and i would like to make a mod in which the player clicks on the rendered map image, it outputs the coordinates to the debug log. For example if i click on the center of the map, the real coordinates should be like 0, 0, 0 but it outputs the screen coordinates, for example my screen's resoluion is 1920x1080, i click on the center, and i get like 960, 540 instead of 0, 0. First i would like to just display the real coordinates where i clicked, i was trying to fix this but i had no idea how i can solve this. Later on i would like to draw a playerblip where the player is being on the map by adding a blip there, and rendering it on the radar, and i don't really know how to solve this too. And of course, later i would like to add other blips. But i would like the blips to match the real coordinates.

I am using MTA San Andreas\MTA\cgui\images\radar.jpg as the radar image.
 

mapVisible = false

toggleControl ("radar", false)

map = {}
map["size"] = 1024

function showMap(button, state)


	if button == "F11" and state == true then
		if mapShown == false then
			mapVisible = true
			addEventHandler ("onClientRender", root, renderMap)
			showCursor (true)
		else
			mapVisible = false
			removeEventHandler ("onClientRender", root, renderMap)
			showCursor (false)
		end
	end


end
addEventHandler ("onClientKey", root, showMap)

x, y = guiGetScreenSize()
mx, my = 1920, 1080

function renderMap()
	dxDrawImage (x/2 - map["size"]/2, y/2 -  map["size"]/2, map["size"], map["size"], "images/map.jpg")
end

function click(button, state, aX, aY) 
	if button == "left" and state == "down" then
		--iprint (x-map["size"])
		iprint (aX - map["size"]) --x y z is not accurate
	end
end
addEventHandler ("onClientClick", root, click)

 

[IIYAMA]

https://wiki.multitheftauto.com/wiki/OnClientClick

string button, string state, int absoluteX, int absoluteY, float worldX, float worldY, float worldZ, element clickedWorld

float worldX, float worldY, float worldZ, element clickedWorld

 

 

https://wiki.multitheftauto.com/wiki/GetScreenFromWorldPosition

 

float float getScreenFromWorldPosition ( float x, float y, float z, [ float edgeTolerance=0, bool relative=true ] )

Edited January 29, 2018 by IIYAMA

[tommymaster]

Thank you, but what i want to do, is click on the image, and get the real x y z coordinates according to the screen position i clicked on the map. Like in the freeroam resource, when i use the map button, select where i want to go, but i don't want to go there, just output the coordinates of the clicked position on the image.

[IIYAMA]

if aX > (x / 2 - map["size"] / 2) and aX < (x / 2 + map["size"] / 2) and aY > (y / 2 - map["size"] / 2) and aY < (y / 2 + map["size"] / 2) then
  
end

 

local clickX = aX - (x / 2 - map["size"] / 2)
local clickY = aY - (y / 2 - map["size"] / 2)

local mapX = clickX / map["size"] * 6000
local mapY = clickY / map["size"] * 6000

 

Everything is untested.

[tommymaster]

Sadly it is still not working. It outputs like 3000 if i click on the center.
 

[IIYAMA]

local mapX = clickX / map["size"] * 6000 - 3000
local mapY = clickY / map["size"] * -6000 + 3000

 

Try this.

Afaik the left + bottom is -3000, -3000. The right + top is 3000, 3000.

And the center is 0, 0.

[tommymaster]

yeah thanks, now it outputs the valid coordinates. but now how can i add blips? i mean i add the blips with create blip, and using "for" i get their positions and blip icons, then draw it on the f11 map using onClientRender, but with what coordinates? could you please write an example for this with commentaries? i learn better from them. 

[NeXuS™]

Using this technic the other way. Getting the screen position from the world position, and drawing it. If you don't try it at all, we ain't gonna give you an example.

[IIYAMA]

map = {
	size = 1024
}

function reCalculateToMap (posX, posY)
	return posX / map["size"] * 6000 - 3000, posY / map["size"] * -6000 + 3000
end

local x, y = reCalculateToMap (500, 800)
print(x, y)


function reCalculateFromMap (mapX, mapY)
	return (mapX + 3000) * map["size"] / 6000, (mapY - 3000) * map["size"] / -6000
end

local x2, y2 = reCalculateFromMap (x, y)

print(x2, y2)

 

This is just old school math.

 

Example:

Click X position in image is: 240px

Image size is: 1024px

Map size is: 6000

X

240 / 1024 = 0.234375 
--[[
	0.234375 * 100 = 23.4
	240 is 23.4% from 1024 
]]

0.234375 * 6000 = 1406.25
--[[
	Append to other value 
    
    ETC.
]]