TextField:getPointFromTextPosition() error when used with TextField:setLayout()

PaulH

This looks like a minor bug. TextField:getPointFromTextPosition() works as expected unless a layout has been applied to the TextField.

Here's some sample code:

-- Put a TextField on the stage:
text = "Here's some text."
font = TTFont.new("Berlin Bold.ttf", 80)
tfx, tfy = 50, 200
tf = TextField.new(font, text)
tf:setPosition(tfx, tfy)
stage:addChild(tf)

-- Add a marker at the last character:
endx, endy = tf:getPointFromTextPosition(string.len(text))
marker = TextField.new(font, "*")
marker:setTextColor(0xff0000)
marker:setPosition(tfx + endx, tfy + endy)
stage:addChild(marker)

-- Put an identical TextField further down the screen but with setLayout:
tfx, tfy = 50, 400
tf = TextField.new(font, text)
tf:setPosition(tfx, tfy)
stage:addChild(tf)
tf:setSample(text)
tf:setLayout({ w = 800, h = 500, lineSpacing = 7, flags=FontBase.TLF_CENTER })

-- Add a marker at the last character:
endx, endy = tf:getPointFromTextPosition(string.len(text))
marker = TextField.new(font, "*")
marker:setTextColor(0xff0000)
marker:setPosition(tfx + endx, tfy + endy)
stage:addChild(marker)

Output:


The first case works as expected. The second positions a marker at the top right of the area defined in the layout. If the text is long enough to be formatted in multiple lines getPointFromTextPosition() returns different values, and I'm not sure what the pattern is, but the result is consistently incorrect.

It's nothing mission-critical, but I thought I should report it.

Cheers,

Paul

MoKaLux

FYI there is also this https://wiki.gideros.rocks/index.php/Examples#A_COLORED_STRING_.40hgy29 to color some part of text

PaulH

Ah yes... thank you! I was trying to find that. I thought that might be another option for what I'm doing, which is adding a blinking "|" character as a cursor when typing text. I could just include the "|" in the TextField and toggle it between the typed text color and the background to blink it.

PaulH

The colored string was in fact an effective way to make a blinking cursor on a multiline TextField. Thanks!

I did notice something odd about that too, though. I had the text field show the "|" character as a cursor on the end, then toggled the alpha back and forth every half second on just the final character to make it blink. That worked, but I saw that the rest of the text changed color when there was any color marker with alpha in the string. I had set the text color #00B (tf:setTextColor(0x0000b0), medium blue) and when the string included the markup to make the cursor character transparent (#0000), the rest of the text darkened to #008 (0x010187 to be precise). It was a bit of an odd effect. To solve it I just included \e[color=#008f] for the cursor when it's visible, so both strings include an alpha specification. All the text is consistently the same blue (#008) that way.

Anyway, cool feature! Thanks for that!

hgy29

PaulH said:

This looks like a minor bug. TextField:getPointFromTextPosition() works as expected unless a layout has been applied to the TextField.

Thanks for reporting that, it seem to be caused by setSample() in the second TF. setSample() doesn't work well with setLayout, I am not sure sure why.

hgy29

PaulH said:

I had set the text color #00B (tf:setTextColor(0x0000b0), medium blue) and when the string included the markup to make the cursor character transparent (#0000), the rest of the text darkened to #008 (0x010187 to be precise).

I just had a look at Gideros code, and there seem to be an issue in that case if you set the textfield color before the text: the color is applied twice: once globally for the textfield and then on each colored text part, so that your #00B becomes #00B * #00B, in practise 11/15 * 11/15, which should give 0x89 for the blue channel.
I'll fix that.

PaulH

Thanks. I assume this is related. If you do this:

tf = TextField.new("hello there")
tf:setText("hello e\[color=#f00]" .. "there" .. "\e[color]")

you get all black text rather than black and red. I assume the constructor for TextField defaults the text color to black (0x000000) if there are no color codes embedded in the text. Then when embedded colors get multiplied by the default text color the result is still black.

If you add tf:setColor(0xffffff) before the setText() call then the embedded colors work, but then any text without a color code becomes white, so "hello" is white and "there" is red in the example.

Adding any color tag to the text passed into the constructor makes everything work, even just \e[color=#000] at the end so it doesn't apply to any text. Then the embedded colors apply to the tagged text and the rest shows in whatever color was specified with setTextColor().

This may be expected behavior. In my case I'll just make sure to include a color code at the end of the text used to create any TextField with which I may later call setText to add colors.

PaulH

Oh, and any call to setText() without an embedded color code seems to reset the default color for that TextField back to 0x000000, so it's not just the constructor it seems.

hgy29

It is a bug, I fixed it earlier;)

PaulH

Cool. Thanks!