/* * call-seq: * rotozoom_size( size, angle, zoom ) -> [width, height] or nil * * Return the dimensions of the surface that would be returned if * #rotozoom() were called on a Surface of the given size, with * the same angle and zoom factors. * * If Rubygame was compiled with SDL_gfx-2.0.13 or greater, +zoom+ can be * an Array of 2 Numerics for separate X and Y scaling. Also, it can be * negative to indicate flipping horizontally or vertically. * * Will return +nil+ if you attempt to use separate X and Y zoom factors * or negative zoom factors with an unsupported version of SDL_gfx. * * This method takes these arguments: * size:: an Array with the hypothetical Surface width and height (pixels) * angle:: degrees to rotate counter-clockwise (negative for clockwise). * zoom:: scaling factor(s). A single positive Numeric, unless you have * SDL_gfx-2.0.13 or greater (see above). */ VALUE rbgm_transform_rzsize(int argc, VALUE *argv, VALUE module) { int w,h, dstw,dsth; double angle, zoomx, zoomy; if(argc < 3) rb_raise(rb_eArgError,"wrong number of arguments (%d for 3)",argc); w = NUM2INT(rb_ary_entry(argv[0],0)); h = NUM2INT(rb_ary_entry(argv[0],0)); angle = NUM2DBL(argv[1]); if(TYPE(argv[2])==T_ARRAY) { /* Separate X/Y rotozoom scaling was not supported prior to 2.0.13. */ /* Check if we have at least version 2.0.13 of SDL_gfxPrimitives */ #ifdef HAVE_ROTOZOOMXY /* Do the real function. */ zoomx = NUM2DBL(rb_ary_entry(argv[1],0)); zoomy = NUM2DBL(rb_ary_entry(argv[1],1)); rotozoomSurfaceSizeXY(w, h, angle, zoomx, zoomy, &dstw, &dsth); #else /* Return nil, because it's not supported. */ return Qnil; #endif } else if(FIXNUM_P(argv[1]) || TYPE(argv[1])==T_FLOAT) { zoomx = NUM2DBL(argv[1]); #ifndef HAVE_ROTOZOOMXY if(zoomx < 0) /* negative zoom (for flipping) */ { /* Return nil, because it's not supported. */ return Qnil; } #endif rotozoomSurfaceSize(w, h, angle, zoomx, &dstw, &dsth); } else rb_raise(rb_eArgError,"wrong zoom factor type (expected Array or Numeric)"); /* if(dstw == NULL || dsth == NULL) rb_raise(eSDLError,"Could not rotozoom surface: %s",SDL_GetError());*/ return rb_ary_new3(2,INT2NUM(dstw),INT2NUM(dsth)); }