我想要实现的功能是这样的:在一张已经打开的图片上点击获取坐标值,然后在指定的两个点间作直线,并在其中右侧的一个指定点上做这条直线的垂线?如何用JavaScript实现呢?
我有划线函数如下:
function LineTo(x,y) {
Line(xo,yo,x,y)
}
function Line(x1,y1,x2,y2) {
x2 = Math.round(x2)
y2 = Math.round(y2)
xo = x2
yo = y2
y1 = orgY(y1)
y2 = orgY(y2)
var str = ""
var i=0
var x = x1
var y = y1
dx = Math.abs(x2-x1)
dy = Math.abs(y2-y1)
s1 = sign(x2-x1)
s2 = sign(y2-y1)
if(dx==0 || dy==0) {
ShowLine(x1,y1,x2-x1,y2-y1)
return
}
if(dx>dy) {
temp = dx
dx = dy
dy = temp
key = 1
}
else
key = 0
e = 2*dy-dx
for(i=0;i<dx;i++) {
px = 0
py = 0
Plot(x,y)
while(e>=0) {
if(key==1) {
x += s1
px += s1
}
else {
y += s2
py += s2
}
e = e-2*dx
}
if(key==1)
y += s2
else
x += s1
e = e+2*dy
}
}
function MoveTo(x,y) {Ox = Oy = -1;xo = Math.round(x);yo = Math.round(y);} 但是调用的时候不知道怎么写?
我有划线函数如下:
function LineTo(x,y) {
Line(xo,yo,x,y)
}
function Line(x1,y1,x2,y2) {
x2 = Math.round(x2)
y2 = Math.round(y2)
xo = x2
yo = y2
y1 = orgY(y1)
y2 = orgY(y2)
var str = ""
var i=0
var x = x1
var y = y1
dx = Math.abs(x2-x1)
dy = Math.abs(y2-y1)
s1 = sign(x2-x1)
s2 = sign(y2-y1)
if(dx==0 || dy==0) {
ShowLine(x1,y1,x2-x1,y2-y1)
return
}
if(dx>dy) {
temp = dx
dx = dy
dy = temp
key = 1
}
else
key = 0
e = 2*dy-dx
for(i=0;i<dx;i++) {
px = 0
py = 0
Plot(x,y)
while(e>=0) {
if(key==1) {
x += s1
px += s1
}
else {
y += s2
py += s2
}
e = e-2*dx
}
if(key==1)
y += s2
else
x += s1
e = e+2*dy
}
}
function MoveTo(x,y) {Ox = Oy = -1;xo = Math.round(x);yo = Math.round(y);} 但是调用的时候不知道怎么写?
解决方案 »
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