BaseDraw.DrawTexture Issue

FlavioDiniz

Hi !
In an attempt to circumvent a bug in the DrawHUDText and DrawMultipleHUDText (link below), I'm trying to use the DrawTexture function, but now we have two issues.
(https://developers.maxon.net/forum/topic/15394/drawhudtext-issue-with-viewport-camera-navigation)

1 - The first issue is the mouse cursor doesn't orbit to the object in the viewport, it's like the text is being drawn in the whole screen and the camera is orbiting around the text... I tested several Zdepth settings. no luck.

2 - The second issue is the lag, notice the difference in C4D 2023 and 2025 in the video below (problem is also present in 2024).

So far I noticed the lag (and the camera orbit issue) on the DrawHUDText, DrawMultipleHUDText and DrawTexture functions. Other simple functions like DrawPoint2D, DrawLine2D and DrawLine does't have issues.

The code I'm using on a tag is:

import c4d
from c4d import plugins, bitmaps, documents

def main() -> None:
    pass

def draw(bd) -> bool:
    bh = c4d.plugins.BaseDrawHelp(bd, doc)
    bd.LineZOffset(2)

    bd.SetMatrix_Screen()

    text = "My Tex asssssssssssssssssssdasdasdt"

    cm = c4d.bitmaps.GeClipMap()
    cm.Init(0, 0, 32)
    cm.BeginDraw()
    width = cm.TextWidth(text)
    height = cm.TextHeight()
    cm.EndDraw()
    cm.Destroy()

    cm.Init(width, height, 32)
    cm.BeginDraw()
    cm.SetColor(255, 255, 255, 255)
    cm.TextAt(0,0,text)
    cm.EndDraw()
    bd.SetMatrix_Screen()
    bd.SetLightList(c4d.BDRAW_SETLIGHTLIST_NOLIGHTS)

    xpos=255
    ypos=255

    padr = [(c4d.Vector(xpos,ypos,0)), (c4d.Vector(xpos+width,ypos,0)), (c4d.Vector(xpos+width,ypos+height,0)), (c4d.Vector(xpos,ypos+height,0))]
    cadr = [(c4d.Vector(1,1,1)), (c4d.Vector(1,1,1)), (c4d.Vector(1,1,1)), (c4d.Vector(1,1,1))]
    vnadr = [(c4d.Vector(0,0,1)), (c4d.Vector(0,0,1)), (c4d.Vector(0,0,1)), (c4d.Vector(0,0,1))]
    uvadr = [(c4d.Vector(0,0,0)), (c4d.Vector(1,0,0)), (c4d.Vector(1,1,0)),(c4d.Vector(0,1,0))]

    cmbmp = bitmaps.BaseBitmap()
    cmbmp = cm.GetBitmap()
    bmp = bitmaps.BaseBitmap()
    bmp = cm.GetBitmap()
    alpha = bmp.GetInternalChannel()               #Get at the RGBA channels of the bitmap copy
    alpha = bmp.AddChannel(True, False)

    bd.SetDepth(False)
    bd.DrawTexture(bmp,padr,cadr,vnadr,uvadr,4,c4d.DRAW_ALPHA_NORMAL,c4d.DRAW_TEXTUREFLAGS_0)

    return True

There's nothing special on the code, we can also see the issue with a simpler code:

import c4d
def main() -> None:
    pass
def draw(bd: c4d.BaseDraw) -> bool:
    bd = doc.GetActiveBaseDraw()
    bd.DrawHUDText(200,200,"TESTING TEXT")

    return c4d.DRAWRESULT_OK

I'm also attaching my C4D file:
draw_hud_text_issue2.c4d

That said, is there any working way to write text to the viewport with Python ?

Thanks in advance !
Flavio Diniz

i_mazlov

Hi Flavio Diniz,

Thank you for providing an extensive description of your issue.

I've updated the original thread about the DrawHUDText issue. I don't see the orbiting center issue anymore after applying the change to the python tag code, namely adding the following early exit condition to the draw function:

    if bd.GetDrawPass() != c4d.DRAWPASS_OBJECT or bd.GetDrawParam(c4d.BASEDRAW_IS_PICK_OBJECT):
        return True

The same thing stands for the lag issue - I cannot reproduce it with the patched python tag code.

Cheers,
Ilia

FlavioDiniz

Fantastic @i_mazlov !
Both issues are solved, thank you so much !

Cheers,
Flavio Diniz