Can anyone Draw an Arrow

BlitzMax Forums/BlitzMax Programming/Can anyone Draw an Arrow

Tibit (Posted 2005) [#1]

To visulize a vector I want to draw a line. Does anyone have a neat function for this?

Diablo (Posted 2005) [#2]

try this wave Graphics 800, 600, 0, 60 While Not KeyHit(KEY_ESCAPE) Cls SetColor 0, 255, 0 DrawArrow 400, 300, MouseX(), MouseY() SetColor 255, 0, 0 DrawArrow MouseX(), MouseY(), 400, 10, 10, 20 SetColor 0, 0, 255 DrawArrow 400, 10, 400, 300, 60, 10 Flip Wend EndGraphics End Function DrawArrow(x1%, y1%, x2%, y2%, _arrowHeadLength% = 20, _arrowHeadWidth% = 10) DrawLine x1, y1, x2, y2 Local lineAngle% = ATan2(x1 - x2, y1 - y2) lineAngle:+ 180 DrawLine x2, y2, (x2 + (Sin(lineAngle * -1) * _arrowHeadLength%)) + (Cos(lineAngle) * _arrowHeadWidth%), (y2 - (Cos(lineAngle * -1) * _arrowHeadLength%)) - (Sin(lineAngle) * _arrowHeadWidth%) DrawLine x2, y2, (x2 + (Sin(lineAngle * -1) * _arrowHeadLength%)) - (Cos(lineAngle) * _arrowHeadWidth%), (y2 - (Cos(lineAngle * -1) * _arrowHeadLength%)) + (Sin(lineAngle) * _arrowHeadWidth%) End Function EDIT: got bord and made a better example (could make a game from this ......) Graphics 800, 600, 0, 60 Type GravBox Field x#, y# Field xspeed#, yspeed# Function Create:GravBox(_x#, _y#) Local tempGravBox:GravBox = New GravBox tempGravBox.x# = _x# tempGravBox.y# = _y# Return tempGravBox End Function Method Update() UpdateMovement() xspeed:* .99 yspeed:+ .05 If y > GraphicsHeight() - 20 Then yspeed = -yspeed / 1.05 UpdateMovement() EndIf If y < 0 Then yspeed = yspeed * -1 UpdateMovement() EndIf If x < 0 Then xspeed:* -1 UpdateMovement() EndIf If x > GraphicsWidth() Then xspeed:* -1 UpdateMovement() EndIf End Method Method UpdateMovement() x:+ xspeed y:+ yspeed End Method End Type Global myGravBox:GravBox = GravBox.Create(GraphicsWidth() / 2, 20) While not KeyHit(KEY_ESCAPE) Cls SetColor 255, 255, 255 DrawOval myGravBox.x - 5, myGravBox.y - 5, 10, 10 SetColor 0, 0, 255 DrawArrow MouseX(), MouseY(),myGravBox.x, myGravBox.y, 5, 5 SetColor 255, 0, 0 DrawArrow myGravBox.x, myGravBox.y,myGravBox.x + (myGravBox.xspeed * 10), myGravBox.y + (myGravBox.yspeed * 10), 20, 5 SetColor 0, 255, 0 DrawArrow myGravBox.x, myGravBox.y,myGravBox.x + ((((MouseX() - myGravBox.x) / 10) * -1)), myGravBox.y + ((((MouseY() - myGravBox.y) / 10) * -1)), 20, 5 SetColor 255, 255, 255 If KeyDown(KEY_LEFT) Then myGravBox.xspeed:- .05 If KeyDown(KEY_RIGHT) Then myGravBox.xspeed:+ .05 If MouseDown(1) Then myGravBox.xspeed:+ (((MouseX() - myGravBox.x) / 1000) * -1) myGravBox.yspeed:+ (((MouseY() - myGravBox.y) / 1000) * -1) End If myGravBox.Update() Flip Wend EndGraphics End Function DrawArrow(x1%, y1%, x2%, y2%, _arrowHeadLength% = 20, _arrowHeadWidth% = 10) DrawLine x1, y1, x2, y2 Local lineAngle% = ATan2(x1 - x2, y1 - y2) lineAngle:+ 180 DrawLine x2, y2, (x2 + (Sin(lineAngle * -1) * _arrowHeadLength%)) + (Cos(lineAngle) * _arrowHeadWidth%), (y2 - (Cos(lineAngle * -1) * _arrowHeadLength%)) - (Sin(lineAngle) * _arrowHeadWidth%) DrawLine x2, y2, (x2 + (Sin(lineAngle * -1) * _arrowHeadLength%)) - (Cos(lineAngle) * _arrowHeadWidth%), (y2 - (Cos(lineAngle * -1) * _arrowHeadLength%)) + (Sin(lineAngle) * _arrowHeadWidth%) End Function enjoy! EDIT 2: YAE (Yet another example) Graphics 800, 600, 32, 60 Type GravBox Field x#, y# Field xspeed#, yspeed# Function Create:GravBox(_x#, _y#) Local tempGravBox:GravBox = New GravBox tempGravBox.x# = _x# tempGravBox.y# = _y# Return tempGravBox End Function Method Update() UpdateMovement() xspeed:* .99 yspeed:+ .09 If y > GraphicsHeight() - 20 Then yspeed = -yspeed / 1.05 UpdateMovement() EndIf If y < 0 Then yspeed = yspeed * -1 UpdateMovement() EndIf If x < 0 Then xspeed:* -1 UpdateMovement() EndIf If x > GraphicsWidth() Then xspeed:* -1 UpdateMovement() EndIf End Method Method UpdateMovement() x:+ xspeed y:+ yspeed End Method End Type Global myGravBox:GravBox = GravBox.Create(GraphicsWidth() / 2, 20) While Not KeyHit(KEY_ESCAPE) Cls SetColor 255, 255, 255 DrawOval myGravBox.x - 5, myGravBox.y - 5, 10, 10 SetColor 0, 0, 255 DrawArrow myGravBox.x, myGravBox.y,myGravBox.x + ((((MouseX() - myGravBox.x) / 5))), myGravBox.y + ((((MouseY() - myGravBox.y) / 5))), 20, 5 SetColor 255, 0, 0 DrawArrow myGravBox.x, myGravBox.y,myGravBox.x + (myGravBox.xspeed * 10), myGravBox.y + (myGravBox.yspeed * 10), 20, 5 SetColor 0, 255, 0 DrawArrow myGravBox.x, myGravBox.y,myGravBox.x + ((((MouseX() - myGravBox.x) / 5) * -1)), myGravBox.y + ((((MouseY() - myGravBox.y) / 5) * -1)), 20, 5 SetColor 255, 255, 255 DrawText "Diablo's Ultra Kool Bouncy Ball Thingy", 10, 10 DrawText "======================================", 10, 20 DrawText "Left Mouse Button: Move ball away from cursor", 10, 30 DrawText "Right Mouse Button: Move ball towards cursor", 10, 40 SetColor 0, 255, 0 DrawArrow 10, 60, 40, 60, 20, 2 DrawText " - Away Vector", 45, 55 SetColor 0, 0, 255 DrawArrow 10, 80, 40, 80, 20, 2 DrawText " - Towards Vector", 45, 75 SetColor 255, 0, 0 DrawArrow 10, 100, 40, 100, 20, 2 DrawText " - Movement Vector", 45, 95 If MouseDown(1) Then myGravBox.xspeed:+ (((MouseX() - myGravBox.x) / 1000) * -1) myGravBox.yspeed:+ (((MouseY() - myGravBox.y) / 1000) * -1) ElseIf MouseDown(2) Then myGravBox.xspeed:- (((MouseX() - myGravBox.x) / 1000) * -1) myGravBox.yspeed:- (((MouseY() - myGravBox.y) / 1000) * -1) End If myGravBox.Update() Flip Wend EndGraphics End Function DrawArrow(x1%, y1%, x2%, y2%, _arrowHeadLength% = 20, _arrowHeadWidth% = 10) DrawLine x1, y1, x2, y2 Local lineAngle% = ATan2(x1 - x2, y1 - y2) lineAngle:+ 180 DrawLine x2, y2, (x2 + (Sin(lineAngle * -1) * _arrowHeadLength%)) + (Cos(lineAngle) * _arrowHeadWidth%), (y2 - (Cos(lineAngle * -1) * _arrowHeadLength%)) - (Sin(lineAngle) * _arrowHeadWidth%) DrawLine x2, y2, (x2 + (Sin(lineAngle * -1) * _arrowHeadLength%)) - (Cos(lineAngle) * _arrowHeadWidth%), (y2 - (Cos(lineAngle * -1) * _arrowHeadLength%)) + (Sin(lineAngle) * _arrowHeadWidth%) End Function

rdodson41 (Posted 2005) [#3]

Nice job Diablo, I only looked at the last one, and I think you mixed up the away vector and toward vector. Toward should be blue, away should be green.

Diablo (Posted 2005) [#4]

Thx Sushimasta, Changed... look above.

Tibit (Posted 2005) [#5]

Thanks! And take a look at MaxPhysics if you get bored again, you might be able to help us out some. :)