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blend_image(3)			 Arcan Lua API			blend_image(3)

NAME
       blend_image - Change image opacity.

SYNOPSIS
       nil
       blend_image( VID	or VIDtbl, opacity, time, interp )

DESCRIPTION
       Changes	the opacity of the selected VID	s either immediately (default)
       or by setting an	optional time  argument	 to  a	non-negative  integer.
       This  function either accepts single VID	s or a group of	VID s in a ta-
       ble (iteration will follow the behavior of pairs() Interp can be	set to
       one of the constants ( INTERP_LINEAR , INTERP_SINE , INTERP_EXPIN , IN-
       TERP_EXPOUT , INTERP_EXPINOUT , INTERP_SMOOTHSTEP ).

NOTES
       1

	      VID s with an opacity other than 0.0 (hidden) and	 1.0  (opaque,
	      visible) will be blended.

       2      Values outside the allowed range will be clamped.

       3      The  blend  behavior is dictated by the default global blendfunc
	      value  (src_alpha,  1-src_alpha)	and  can  be  overridden  with
	      force_image_blend(mode)

EXAMPLE
       function	blend_image0()
	     a = fill_surface(128, 128,	255, 0,	0);
	     b = fill_surface(128, 128,	0, 255,	0);
	     move_image(b, 64, 64);
	     show_image({a,b});
	     blend_image(b, 0.5, 100);
       end

MISUSE
       function	blend_image0()
	     a = fill_surface(128, 128,	255, 0,	0);
	     b = fill_surface(128, 128,	0, 255,	0);
	     move_image(b, 64, 64);
	     show_image({a,b});
	     blend_image(b, -0.5, -100);
       end

MISUSE
       function	blend_image1()
	     a = fill_surface(128, 128,	255, 0,	0);
	     b = fill_surface(128, 128,	0, 255,	0);
	     move_image(b, 64, 64);
	     show_image({a,b});
	     blend_image("a", 0.5, 100);
       end

MISUSE
       function	blend_image2()
	     a = fill_surface(128, 128,	255, 0,	0);
	     b = fill_surface(128, 128,	0, 255,	0);
	     move_image(b, 64, 64);
	     show_image({a,b});
	     blend_image({-1, "a", true, 5.0}, true, "error");
       end

SEE ALSO:
       image_force_blend(3)

image				  April	2025			blend_image(3)

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