view docs/man3/SDL_JoyButtonEvent.3 @ 3333:b334b4f7dfa0

[SDL] Bad math in SDL_RenderCopy Mason Wheeler to sdl When I tried to render an image using something other than NULL for srcrect, it got horribly distorted. I traced it down to the fact that the math in the rectangle adjustments performed just before the call to renderer->RenderCopy is written inside out. It should look like this: if (dstrect->w != real_dstrect.w) { int deltax = (dstrect->x - real_dstrect.x); int deltaw = (dstrect->w - real_dstrect.w); real_srcrect.x += (deltax * real_srcrect.w) / dstrect->w; real_srcrect.w += (deltaw * real_srcrect.w) / dstrect->w; } if (dstrect->h != real_dstrect.h) { int deltay = (dstrect->y - real_dstrect.y); int deltah = (dstrect->h - real_dstrect.h); real_srcrect.y += (deltay * real_srcrect.h) / dstrect->h; real_srcrect.h += (deltah * real_srcrect.h) / dstrect->h;
author Sam Lantinga <slouken@libsdl.org>
date Sat, 03 Oct 2009 16:23:16 +0000
parents 546f7c1eb755
children 1238da4a7112
line wrap: on
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.TH "SDL_JoyButtonEvent" "3" "Tue 11 Sep 2001, 22:59" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_JoyButtonEvent \- Joystick button event structure
.SH "STRUCTURE DEFINITION"
.PP
.nf
\f(CWtypedef struct{
  Uint8 type;
  Uint8 which;
  Uint8 button;
  Uint8 state;
} SDL_JoyButtonEvent;\fR
.fi
.PP
.SH "STRUCTURE DATA"
.TP 20
\fBtype\fR
\fBSDL_JOYBUTTONDOWN\fP or \fBSDL_JOYBUTTONUP\fP
.TP 20
\fBwhich\fR
Joystick device index
.TP 20
\fBbutton\fR
Joystick button index
.TP 20
\fBstate\fR
\fBSDL_PRESSED\fP or \fBSDL_RELEASED\fP
.SH "DESCRIPTION"
.PP
\fBSDL_JoyButtonEvent\fR is a member of the \fI\fBSDL_Event\fR\fR union and is used when an event of type \fBSDL_JOYBUTTONDOWN\fP or \fBSDL_JOYBUTTONUP\fP is reported\&.
.PP
A \fBSDL_JOYBUTTONDOWN\fP or \fBSDL_JOYBUTTONUP\fP event occurs when ever a user presses or releases a button on a joystick\&. The field \fBwhich\fR is the index of the joystick that reported the event and \fBbutton\fR is the index of the button (for a more detailed explaination see the \fIJoystick section\fR)\&. \fBstate\fR is the current state or the button which is either \fBSDL_PRESSED\fP or \fBSDL_RELEASED\fP\&.
.SH "SEE ALSO"
.PP
\fI\fBSDL_Event\fR\fR, \fIJoystick Functions\fR, \fI\fBSDL_JoystickEventState\fP\fR, \fI\fBSDL_JoystickGetButton\fP\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 22:59