Having difficulties finding if my mouse is in a triangle.

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Relativity

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Joined: 29th Mar 2005

Location: Position is relative.

Posted: 15th Jul 2005 12:51 Edited at: 16th Jul 2005 04:24

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This is part of a larger program. Basically what I want to do is detect when my mouse is within the triangular area of three objects. If the mouse is within the area then a triangle should be drawn between the three objects. However, I am having difficulties. Sometimes when I am outside the area the triangle is drawn and sometimes when I am within the area the triangle isn't drawn. I've looked over the code several times and can't find anything wrong with it

AUTOCAM OFF
SYNC ON

MAKE OBJECT SPHERE 1,0
MAKE OBJECT SPHERE 2,5
MAKE OBJECT SPHERE 3,5
MAKE OBJECT SPHERE 4,5

POSITION OBJECT 1,0,0,0
POSITION OBJECT 2,0,0,20
POSITION OBJECT 3,5,0,10
POSITION OBJECT 4,-5,0,10

DO
   POSITION MOUSE 400,300

MLOOKX#=WRAPVALUE(MLOOKX#+MOUSEMOVEY())
   MLOOKY#=WRAPVALUE(MLOOKY#+MOUSEMOVEX())

IF MLOOKX#>180 AND MLOOKX#<270 THEN MLOOKX#=270
   IF MLOOKX#<180 AND MLOOKX#>90 THEN MLOOKX#=90

ROTATE OBJECT 1,MLOOKX#,MLOOKY#,0

IF UPKEY()=1 THEN MOVE OBJECT 1,10.0
   IF DOWNKEY()=1 THEN MOVE OBJECT 1,-10.0

POSITION CAMERA OBJECT POSITION X(1),OBJECT POSITION Y(1),OBJECT POSITION Z(1)
   ROTATE CAMERA OBJECT ANGLE X(1),OBJECT ANGLE Y(1),OBJECT ANGLE Z(1)

OBJNUM=2
      OBJNUM2=3
      OBJNUM3=4

IF OBJECT SCREEN X(OBJNUM)=OBJECT SCREEN X(OBJNUM2)
         IF OBJECT SCREEN X(OBJNUM)>OBJECT SCREEN X(OBJNUM3)
            IF OBJECT SCREEN X(OBJNUM)<MOUSEX() THEN GOTO NEXTTEX1
         ELSE
            IF OBJECT SCREEN X(OBJNUM)>MOUSEX() THEN GOTO NEXTTEX1
         ENDIF
      ELSE
         SLOPE#=(OBJECT SCREEN Y(OBJNUM)-OBJECT SCREEN Y(OBJNUM2))/(OBJECT SCREEN X(OBJNUM)-OBJECT SCREEN X(OBJNUM2))
         YINT#=OBJECT SCREEN Y(OBJNUM)-(SLOPE#*OBJECT SCREEN X(OBJNUM))
         IF YINT#>OBJECT SCREEN Y(OBJNUM3)-(SLOPE#*OBJECT SCREEN X(OBJNUM3))
            IF YINT#<MOUSEY()-(SLOPE#*MOUSEX()) THEN GOTO NEXTTEX1
         ELSE
            IF YINT#>MOUSEY()-(SLOPE#*MOUSEX()) THEN GOTO NEXTTEX1
         ENDIF
      ENDIF

IF OBJECT SCREEN X(OBJNUM)=OBJECT SCREEN X(OBJNUM3)
         IF OBJECT SCREEN X(OBJNUM)>OBJECT SCREEN X(OBJNUM2)
            IF OBJECT SCREEN X(OBJNUM)<MOUSEX() THEN GOTO NEXTTEX1
         ELSE
            IF OBJECT SCREEN X(OBJNUM)>MOUSEX() THEN GOTO NEXTTEX1
         ENDIF
      ELSE
         SLOPE#=(OBJECT SCREEN Y(OBJNUM)-OBJECT SCREEN Y(OBJNUM3))/(OBJECT SCREEN X(OBJNUM)-OBJECT SCREEN X(OBJNUM3))
         YINT#=OBJECT SCREEN Y(OBJNUM)-(SLOPE#*OBJECT SCREEN X(OBJNUM))
         IF YINT#>OBJECT SCREEN Y(OBJNUM2)-(SLOPE#*OBJECT SCREEN X(OBJNUM2))
            IF YINT#<MOUSEY()-(SLOPE#*MOUSEX()) THEN GOTO NEXTTEX1
         ELSE
            IF YINT#>MOUSEY()-(SLOPE#*MOUSEX()) THEN GOTO NEXTTEX1
         ENDIF
      ENDIF

IF OBJECT SCREEN X(OBJNUM2)=OBJECT SCREEN X(OBJNUM3)
         IF OBJECT SCREEN X(OBJNUM2)>OBJECT SCREEN X(OBJNUM)
            IF OBJECT SCREEN X(OBJNUM2)<MOUSEX() THEN GOTO NEXTTEX1
         ELSE
            IF OBJECT SCREEN X(OBJNUM2)>MOUSEX() THEN GOTO NEXTTEX1
         ENDIF
      ELSE
         SLOPE#=(OBJECT SCREEN Y(OBJNUM2)-OBJECT SCREEN Y(OBJNUM3))/(OBJECT SCREEN X(OBJNUM2)-OBJECT SCREEN X(OBJNUM3))
         YINT#=OBJECT SCREEN Y(OBJNUM2)-(SLOPE#*OBJECT SCREEN X(OBJNUM2))
         IF YINT#>OBJECT SCREEN Y(OBJNUM)-(SLOPE#*OBJECT SCREEN X(OBJNUM))
            IF YINT#<MOUSEY()-(SLOPE#*MOUSEX()) THEN GOTO NEXTTEX1
         ELSE
            IF YINT#>MOUSEY()-(SLOPE#*MOUSEX()) THEN GOTO NEXTTEX1
         ENDIF
      ENDIF

LINE OBJECT SCREEN X(2),OBJECT SCREEN Y(2),OBJECT SCREEN X(3),OBJECT SCREEN Y(3)
      LINE OBJECT SCREEN X(3),OBJECT SCREEN Y(3),OBJECT SCREEN X(4),OBJECT SCREEN Y(4)
      LINE OBJECT SCREEN X(4),OBJECT SCREEN Y(4),OBJECT SCREEN X(2),OBJECT SCREEN Y(2)

NEXTTEX1:

SYNC
LOOP

+ Code Snippet

AUTOCAM OFF
SYNC ON

MAKE OBJECT SPHERE 1,0
MAKE OBJECT SPHERE 2,5
MAKE OBJECT SPHERE 3,5
MAKE OBJECT SPHERE 4,5

POSITION OBJECT 1,0,0,0
POSITION OBJECT 2,0,0,20
POSITION OBJECT 3,5,0,10
POSITION OBJECT 4,-5,0,10


DO
   POSITION MOUSE 400,300

   MLOOKX#=WRAPVALUE(MLOOKX#+MOUSEMOVEY())
   MLOOKY#=WRAPVALUE(MLOOKY#+MOUSEMOVEX())

   IF MLOOKX#>180 AND MLOOKX#<270 THEN MLOOKX#=270
   IF MLOOKX#<180 AND MLOOKX#>90 THEN MLOOKX#=90

   ROTATE OBJECT 1,MLOOKX#,MLOOKY#,0

   IF UPKEY()=1 THEN MOVE OBJECT 1,10.0
   IF DOWNKEY()=1 THEN MOVE OBJECT 1,-10.0

   POSITION CAMERA OBJECT POSITION X(1),OBJECT POSITION Y(1),OBJECT POSITION Z(1)
   ROTATE CAMERA OBJECT ANGLE X(1),OBJECT ANGLE Y(1),OBJECT ANGLE Z(1)

      OBJNUM=2
      OBJNUM2=3
      OBJNUM3=4

      IF OBJECT SCREEN X(OBJNUM)=OBJECT SCREEN X(OBJNUM2)
         IF OBJECT SCREEN X(OBJNUM)>OBJECT SCREEN X(OBJNUM3)
            IF OBJECT SCREEN X(OBJNUM)<MOUSEX() THEN GOTO NEXTTEX1
         ELSE
            IF OBJECT SCREEN X(OBJNUM)>MOUSEX() THEN GOTO NEXTTEX1
         ENDIF
      ELSE
         SLOPE#=(OBJECT SCREEN Y(OBJNUM)-OBJECT SCREEN Y(OBJNUM2))/(OBJECT SCREEN X(OBJNUM)-OBJECT SCREEN X(OBJNUM2))
         YINT#=OBJECT SCREEN Y(OBJNUM)-(SLOPE#*OBJECT SCREEN X(OBJNUM))
         IF YINT#>OBJECT SCREEN Y(OBJNUM3)-(SLOPE#*OBJECT SCREEN X(OBJNUM3))
            IF YINT#<MOUSEY()-(SLOPE#*MOUSEX()) THEN GOTO NEXTTEX1
         ELSE
            IF YINT#>MOUSEY()-(SLOPE#*MOUSEX()) THEN GOTO NEXTTEX1
         ENDIF
      ENDIF

      IF OBJECT SCREEN X(OBJNUM)=OBJECT SCREEN X(OBJNUM3)
         IF OBJECT SCREEN X(OBJNUM)>OBJECT SCREEN X(OBJNUM2)
            IF OBJECT SCREEN X(OBJNUM)<MOUSEX() THEN GOTO NEXTTEX1
         ELSE
            IF OBJECT SCREEN X(OBJNUM)>MOUSEX() THEN GOTO NEXTTEX1
         ENDIF
      ELSE
         SLOPE#=(OBJECT SCREEN Y(OBJNUM)-OBJECT SCREEN Y(OBJNUM3))/(OBJECT SCREEN X(OBJNUM)-OBJECT SCREEN X(OBJNUM3))
         YINT#=OBJECT SCREEN Y(OBJNUM)-(SLOPE#*OBJECT SCREEN X(OBJNUM))
         IF YINT#>OBJECT SCREEN Y(OBJNUM2)-(SLOPE#*OBJECT SCREEN X(OBJNUM2))
            IF YINT#<MOUSEY()-(SLOPE#*MOUSEX()) THEN GOTO NEXTTEX1
         ELSE
            IF YINT#>MOUSEY()-(SLOPE#*MOUSEX()) THEN GOTO NEXTTEX1
         ENDIF
      ENDIF

      IF OBJECT SCREEN X(OBJNUM2)=OBJECT SCREEN X(OBJNUM3)
         IF OBJECT SCREEN X(OBJNUM2)>OBJECT SCREEN X(OBJNUM)
            IF OBJECT SCREEN X(OBJNUM2)<MOUSEX() THEN GOTO NEXTTEX1
         ELSE
            IF OBJECT SCREEN X(OBJNUM2)>MOUSEX() THEN GOTO NEXTTEX1
         ENDIF
      ELSE
         SLOPE#=(OBJECT SCREEN Y(OBJNUM2)-OBJECT SCREEN Y(OBJNUM3))/(OBJECT SCREEN X(OBJNUM2)-OBJECT SCREEN X(OBJNUM3))
         YINT#=OBJECT SCREEN Y(OBJNUM2)-(SLOPE#*OBJECT SCREEN X(OBJNUM2))
         IF YINT#>OBJECT SCREEN Y(OBJNUM)-(SLOPE#*OBJECT SCREEN X(OBJNUM))
            IF YINT#<MOUSEY()-(SLOPE#*MOUSEX()) THEN GOTO NEXTTEX1
         ELSE
            IF YINT#>MOUSEY()-(SLOPE#*MOUSEX()) THEN GOTO NEXTTEX1
         ENDIF
      ENDIF

      LINE OBJECT SCREEN X(2),OBJECT SCREEN Y(2),OBJECT SCREEN X(3),OBJECT SCREEN Y(3)
      LINE OBJECT SCREEN X(3),OBJECT SCREEN Y(3),OBJECT SCREEN X(4),OBJECT SCREEN Y(4)
      LINE OBJECT SCREEN X(4),OBJECT SCREEN Y(4),OBJECT SCREEN X(2),OBJECT SCREEN Y(2)

      NEXTTEX1:

      SYNC
LOOP

Please tell me if you can figure out my problem.
P.S. Everything above the OBJNUM=2 : OBJNUM2=3... is mostly camera movement for you benefit. What I am having trouble with is underneath.

"It's against my programming to impersonate a deity!"~C-3P0

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Link102

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Joined: 1st Dec 2004

Location: On your head, weeeeee!

Posted: 15th Jul 2005 22:11 Edited at: 15th Jul 2005 22:13

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I taking a looksee at your program, but I don't understand this piece of code:

+ Code Snippet

IF OBJECT SCREEN X(OBJNUM)>OBJECT SCREEN X(OBJNUM3)
            IF OBJECT SCREEN X(OBJNUM)<MOUSEX() THEN GOTO NEXTTEX1
         ELSE
            IF OBJECT SCREEN X(OBJNUM)>MOUSEX() THEN GOTO NEXTTEX1
         ENDIF

they both basicly do the same thing, why?

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Sven B

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Location: Belgium

Posted: 15th Jul 2005 22:19

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because it has to do somthing when the mouse is NOT in that area.

I would compress it a little though...

+ Code Snippet

IF OBJECT SCREEN X(OBJNUM)>OBJECT SCREEN X(OBJNUM3)
    IF OBJECT SCREEN X(OBJNUM)<MOUSEX() OR IF OBJECT SCREEN X(OBJNUM)>MOUSEX() 
       GOTO NEXTTEX1
    ENDIF
ENDIF

Immunity and Annihalation makes Immunihalation...

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Relativity

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Location: Position is relative.

Posted: 16th Jul 2005 01:21

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I can't compress it like that. I think you overlooked the "else" statement. This particular sequence of code is only used if two objects make a vertical line on the 2D screen. This would create an infinite slope, thus the reason for the extra sequence. In English it basically means that if the x position of one object in the vertical line (since both of their x's are the same I only need one) is greater than the x position of the third object in the triangle, and if the x position of an object in the line is less than the x position of the mouse then the mouse obviously is not within the bounds of the triangle. The else statement is the same thing only reverse the < and > signs.

"It's against my programming to impersonate a deity!"~C-3P0

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Sven B

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Posted: 16th Jul 2005 01:23

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Mmmm, ic... nvm then..

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Relativity

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Posted: 16th Jul 2005 08:47

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I think I figured out what at least part of the problem is. My slope# and yint# are always coming out whole numbers. Most of the time they should be very extended decimals. I thought this would have been taken care of with the "#" signs, but I guess not. How can I fix this?

"It's against my programming to impersonate a deity!"~C-3P0

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Relativity

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Posted: 17th Jul 2005 02:05

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Ok, it's working now. Instead of doing the slope in one step, I now have

+ Code Snippet

CHNGY#=OBJECT SCREEN Y(OBJNUM)-OBJECT SCREEN Y(OBJNUM2)
CHNGX#=OBJECT SCREEN X(OBJNUM)-OBJECT SCREEN Y(OBJNUM2)
SLOPE#=CHNGY#/CHNGX#

"It's against my programming to impersonate a deity!"~C-3P0

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