hello all, i newbie here.
i create 3D RPG style game with glbasic.
the style is point n click movement, but still in progress now.
i got some problem with X_SCREEN2WORLD syntax.
i very clear at X_WORLD2SCREEN syntax, n i got right return value with that,
but not from X_SCREEN2WORLD syntax. this syntax give me wrong return value.
i know, X_WORLD2SCREEN syntax is for converts 3D coordinates to 2D screen coordinates, and
X_SCREEN2WORLD syntax for converts 2D screen coordinates to 3D coordinates.
only with X_SCREEN2WORLD syntax i got wrong return value. is that bug or what?
or maybie all of u have sample code for that? or alternative code or something?
pls help me...
thx
( sry for my bad english, i'm from indonesia =D )
It should work. Make sure you call that after X_MAKE3D and after X_CAMERA.
Just perform an X_LINE with the coordinated returned to check if it's OK.
If not, make a small example program.
Quote from: Kitty Hello on 2010-Jun-18
It should work. Make sure you call that after X_MAKE3D and after X_CAMERA.
Just perform an X_LINE with the coordinated returned to check if it's OK.
If not, make a small example program.
thx for reply.
here my sample source:
//== INIT ==
GLOBAL mouse_stat_x,mouse_stat_y,mouse_stat_a,mouse_stat_b,screen_x,screen_y,screen_z
SETCURRENTDIR("Media")
//==========
//== TERRAIN ==
// terrain object
X_OBJSTART 0
f=RGB(255,255,255)
X_OBJADDVERTEX -2000,0,-2000, 0 ,0,f
X_OBJADDVERTEX 2000,0,-2000, 50, 0,f
X_OBJADDVERTEX -2000,0, 2000, 0,50,f
X_OBJADDVERTEX 2000,0, 2000, 50,50,f
X_OBJEND
// terrain texture
LOADSPRITE "gras.bmp", 0
//=============
//== MOUSE CURSOR IMAGE ==
LOADSPRITE "cursor.png", 1
//========================
//== 3d object - Sphere ==
CreateSphere(2, 5, 15, RGB(255, 0, 0));
//========================
//== MAIN LOOP ==
WHILE TRUE
//DRAWRECT 0,0,640,480,RGB(0,255,255)
X_MAKE3D 1, 1200, 45
X_CAMERA 100,100,100,0,0,0
X_DRAWAXES 0,0,0
//-- terrain --
X_MOVEMENT 0,0,0
X_SETTEXTURE 0, -1
X_DRAWOBJ 0,0
//-- put 3D object sphere for init coordinate
X_DRAWOBJ 2,0
//-- move 3D object Sphere at mouse XY [left click event]
// IF MOUSEAXIS(3)
// ENDIF
//-- get mouse stat --
MOUSESTATE mouse_stat_x,mouse_stat_y,mouse_stat_a,mouse_stat_b
//-- convert mouse screen coordinat to 3d world
X_SCREEN2WORLD mouse_stat_x,mouse_stat_y,0,screen_x,screen_y,screen_z
//-- 2D part --
X_MAKE2D
//-- text font output --
LOADFONT "font.png", 1
SETFONT 1
PRINT "Screen XY : " + mouse_stat_x +"/"+mouse_stat_y, 0, 0
PRINT "3Dworld XY: "+INTEGER(screen_x)+"/"+INTEGER(screen_y)+"/"+INTEGER(screen_z), 0 ,15
//-- mouse cursor image -> move by mouse stat coordinate
ZOOMSPRITE 1,mouse_stat_x,mouse_stat_y,0.5,0.5
SHOWSCREEN
WEND
//===============
END
//== FUNCTION ==
FUNCTION CreateSphere: num, r, n, col
LOCAL i,j, theta1, theta2, theta3, pi
pi = ACOS(0)*2
IF r < 0 THEN r = -r
IF n < 3 THEN n = 3
X_OBJSTART num
FOR j=0 TO n/2-1
theta1 = j * 2*pi / n - pi/2;
theta2 = (j + 1) * 2*pi / n - pi/2;
FOR i=0 TO n
theta3 = i * 2*pi / n;
X_OBJADDVERTEX r*COS(theta2) * COS(theta3), r*SIN(theta2), _
r*COS(theta2) * SIN(theta3), i/n, 2*(j+1)/n, col
X_OBJADDVERTEX r*COS(theta1) * COS(theta3), r*SIN(theta1), _
r*COS(theta1) * SIN(theta3), i/n, 2*j/n, col
NEXT
X_OBJNEWGROUP
NEXT
X_OBJEND
ENDFUNCTION
//==============
(http://i45.tinypic.com/fjow21.gif)
now i understand.
with "X_LINE" returned right value, thx for help :D.
#at my sample above, i was use "print" to show value at 2D text, thats wrong way.
but...
thats coordinate not what i mean. i must get coordinat at 3D terrain, this is for target movement for my char object. maybie i must calc for that ( using Trigonometry, ach.. :'( )
After the SCREEN2WORLD use the gained vectors and do an X_COLLISIONRAY on the ground. You get the length of the "direction" from that point to the collision point. Then simply do:
mouse_pos_3d + mouse_z_direction * distance_to_collision
and you have the 3D point of the mesh under the mouse.
Quote from: Kitty Hello on 2010-Jun-24
After the SCREEN2WORLD use the gained vectors and do an X_COLLISIONRAY on the ground. You get the length of the "direction" from that point to the collision point. Then simply do:
mouse_pos_3d + mouse_z_direction * distance_to_collision
and you have the 3D point of the mesh under the mouse.
thx for reply..
but i still not get it :(, can u show sample code for that? ( full sample code if u mind =D )
btw,
here my game:(http://i50.tinypic.com/23kp5e8.gif)
i used 3D object as mouse picking, but not from mouse XY screen coordinate ;).
the problem is, how to pick 2D image on screen like inventory list,menu,spell,etc.
that why i realy need how to convert mouse xy screen to 3D world as mouse pick.
thx b4
You can't just convert 2D to 3D, you need to figure out where in the world your mousepointer is pointing. And this you do with X_COLLISIONRAY. There is an example with code in the help, look up the command X_COLLISIONRAY.