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                             The PLLB-C2P Demo's

                   Written (hacked together) by Kevin Picone

            (c) copyright 1996, Kevin Picone, Of Underware Design

                         Lasted Updated: 27-4-1996

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 Zrotate/Flexer:   256/64 & 16 colours, 320*256, Pixel Res of 1x*2y
 ===============

 With this routine and the type of image that it uses, I've selected
 to use the Normal Pllb-C2P mode in all three demos.  If the Image was
 less complex (ie. more solid colour areas) or moved less, well I would
 have been better suited to use the DELTA modes.

 Unfortunately, the code that renders the rotated Scanlines is quite slow.
 Here is an example of the code render just a single pixel in the rotated
 line.

 ; a0 = pointer to chunky buffer
 ; a2 ='s pointer to Picture's address ie. picture is (256*256 pixels)

 ;	Render Pixel	

	move.w d2,d4		; backup X position
	move.w d3,d5		: Backup Y position

	lsr.w #8,d4		; shift x position into lower Byte 
	move.b d4,d5		; move X position into y pos

	move.b (a2,d5.l),(a0)+		; Grab & output pixel

	add.w d0,d2		; add X fraction to X offset!
	add.w d1,d3		; add Y fraction to Y offset!


 On my A1200/020 14mhz+fastram it's runs at an Average of 6.8 Fps





 Gouraud Cube:     256 colours, 320*256, Pixel Res of 1x*2y 
 =============

 In these little demos, I've selected to use a both the NULLSKIP C2P,
 and the new DELTANULLSKIP c2p routines, which are denoted NS & DNS
 respectively in the filenames. I've select these since there is obviously
 quite a large amount of unused screen space, and not to mention that
 this C2P mode also clears the chunky buffer for me.

 Unfortunately again, the Gouraud code is extremely slow, with the inner
 draw gouraud scanline loop looking something like this..
 
 DrawGouraudScanLine_lp:
            move.w d4,d0
            lsr.w #8,d0
            move.b d0,(a5)+
            add.w d5,d4

        dbf d7,DrawGouraudScanLine_lp


 On my A1200/020 14mhz+fastram it's runs at an Average of 14.2 Fps


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