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for the saturn, how would i do transparency?

mrkotfw - May 6, 2003

		mrkotfw		May 6, 2003
			like............. how would i do fade? sorry for the stupid questions but i need to learn how... also... how would i delete a screen? like if i have a function that has 3d and like 100 secs later i want to show another 3d or 2d? like [func_showing_3d] [fade] [delete func_show_3d from screen] [show_2d_func] ? i'll ummm sign up to the contest in a few days, my demo is not ready yet..... BTW my 3d textures show in 3d editor nice and cool but when they are shown are the saturn they look diffrent, like corrupted, old (not the figure) but the textures... WHY? i get that alot, my 1st demo NESCPHP did that. also My name changed from NESCPHP to EL PIRATERO so Slinga nescphp is out sorry for the nick change and thanks for that shout out... bye :devil

		antime		May 7, 2003
			At least on the hardware level, all parts (sprites, polygons, VDP2 backgrounds) can be set to blend with the VDP2 line screen. Enabling that feature and then fading the colour of the line screen would be a cheap way of doing it. Other ways include: - single-colour polygons are trivial - for paletted textures, fade the palettes - enable gouraud shading and fade the gouraud setting - blend to another VDP2 background, not the line screen - paint over the screen repeatedly with half-transparent polygons (each pass will reduce brightness in half, if you use black) - others?

		Djidjo		May 7, 2003
			Don't know abaout transparency, but if you want to clear the screen, you just have not to draw anything anymore, and the screen will be blank. while... { slPutPolygon... ... slSynch(); } while... { slPutPolygon... //another polygon will be shown, and not the first one. ... slSynch(); }

vreuzon

May 7, 2003

	
	
		
		
			if you want to clear the screen, you just have not to draw anything anymore, and the screen will be blank.

It is not the case for slPrint("X"). X will still be displayed after a slSynch() if the screen is not explicitly blanked.

antime :

- "half-transparent polygons" : can you do such things using the SGL ? How

- do you understand values stored in the gouraud table ?

antime

May 7, 2003

	
	
		
		
			Originally posted by vreuzon@May 7, 2003 @ 03:13 PM



- "half-transparent polygons" : can you do such things using the SGL ? How

No idea. Check the docs.

	
	
		
		
			- do you understand values stored in the gouraud table ?

If I've understood correctly, the values indicate what value should be added to or subtracted from the RGB values at each vertex. These values are then interpolated across the polygon. The modification value is 5 bits and is specified for each colour component separately, see the table on page 65 of the VDP1 manual to see the possible values and their meaning. (Actually, since the modification values are limited from -0x10 to +0xf you can't fade completely to black using only that method. Sorry about the misinformation.)

		Reinhart		May 7, 2003
			I manage to made a transparent cube by applying ntexture on it (see it in the SatDev progz section...) It works the same way sprites are transparent. From a pic created with 'ssconv' replace (in the .c file) the first hexadecimal value by 0x0000. I have no idea how to do a 'fade effect', for the 'clear screen' thing ... why bot put the display fonction into a timer ? if timer < 100s display polygon1 if timer<200 timer>101 do_nothing if timer<300 timer>201 display polygon2 Does it sound lame ?

		mrkotfw		May 7, 2003
			thanks, i guess i can just use slSynch(); :agree it is true, slPrint does not clear... maybe we can find a register and make a function out of it or find all registers to display VDP2\|VDP1 and set them to 0 then set them back when we want to display something? like empty(); ? or unset(); but hey, what about my cube? why doesnt it show correctly? does anyone know why? i make a orange textured cube and it comes out as white... oh BTW, the saturn programs are 404 on each one! i need some source ;( reinhart whats your site again? oh and i need a partner for the contest! anyone willing to be my partner... someone who is dedicated and is on mIRC, oh hey, ummmm how would i mix 2d background with 3d? i tried but it justs keep blinking... oh...has anyone messed with the saturn sound? :devil :edit :bs -----------> -> hey umm if you want to be my partner just /msg piratero on EFNET

		mrkotfw		May 7, 2003
			Cel2VRAM(ex_2d_cel,(void )NBG1_CEL_ADR,31808); Map2VRAM(ex_2d_map,(void )NBG1_MAP_ADR,32,16,1,256); Pal2CRAM(ex_2d_pal,(void *)NBG1_COL_ADR,256); it shows it all corrupted........... on the docs it says that it asks for the chara_size.............? how would i figure that out? that confuses me