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</o:shapelayout></xml><![endif]--></head><body lang=DE-CH link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoPlainText><span lang=DE> <o:p></o:p></span></p><p class=MsoPlainText><span lang=DE> >Before implementing clipping in HW you would have to implement these<o:p></o:p></span></p><p class=MsoPlainText><span lang=DE> >primitives in HW.<o:p></o:p></span></p><p class=MsoPlainText><span lang=DE> <o:p></o:p></span></p><p class=MsoPlainText><span lang=DE> Did you mean these primitives implemented in SW [HW], to clip them in<o:p></o:p></span></p><p class=MsoPlainText><span lang=DE> HW?<o:p></o:p></span></p><p class=MsoPlainText><span lang=DE><o:p> </o:p></span></p><p class=MsoPlainText><span lang=EN-US style='color:#4472C4'>No. HW primitives can be clipped in HW or SW. SW primitives to be clipped in SW.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-US> <o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-US> </span><span lang=DE>My naive idea of HW clip would be, to populate HW registers with F.X,<o:p></o:p></span></p><p class=MsoPlainText><span lang=DE> F.Y, F.X+F.W, F.Y+F.H.<o:p></o:p></span></p><p class=MsoPlainText><span lang=DE> <o:p></o:p></span></p><p class=MsoPlainText><span lang=DE> Then some `magic' address calculation blocks will let through to<o:p></o:p></span></p><p class=MsoPlainText><span lang=DE> display buffer only certain mem access. Nothing to be drawn outside<o:p></o:p></span></p><p class=MsoPlainText><span lang=DE> bounds.<o:p></o:p></span></p><p class=MsoPlainText><span lang=DE style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText><span lang=EN-US style='color:#4472C4'>Unfortunately, that's not easily possible, as memory wraps around from line to line. A simple test "if point is inside allowed region" is not enough.<o:p></o:p></span></p><p class=MsoPlainText><span lang=DE style='color:black'><img width=225 height=84 style='width:2.3437in;height:.875in' id="Grafik_x0020_1" src="cid:image001.png@01D4D271.F8BB7840"></span><span lang=EN-US style='color:black'><o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-US style='color:#4472C4'>For HW to clip, you need a Line primitive in HW. A simple Dot primitive in HW checking for memory bounds is not enough.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-US style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText><span lang=EN-US> <o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-US> </span><span lang=DE>-- <o:p></o:p></span></p><p class=MsoPlainText><span lang=DE> Tomas Kral <thomas.kral@email.cz><o:p></o:p></span></p><p class=MsoPlainText><span lang=DE> --<o:p></o:p></span></p><p class=MsoPlainText><span lang=DE> Oberon@lists.inf.ethz.ch mailing list for ETH Oberon and related systems<o:p></o:p></span></p><p class=MsoPlainText><span lang=DE> https://lists.inf.ethz.ch/mailman/listinfo/oberon<o:p></o:p></span></p><p class=MsoPlainText><span lang=DE> <o:p></o:p></span></p></div></body></html>