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Changed complicated push/pull to simple EOR to choose a page

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Rob McMullen 2017-07-03 16:31:35 -07:00
parent 22d12dc34f
commit 41ce921322
1 changed files with 15 additions and 32 deletions
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47
HiSprite.py
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@ -352,8 +352,6 @@ class Sprite(Listing):
optimizationCount = 0
order = list(range(self.height))
if self.double_buffer:
order = reversed(order)
for row in order:
cycleCount += self.rowStartCalculatorCode(row, baselabel)
@ -412,41 +410,26 @@ class Sprite(Listing):
return cycleCount, optimizationCount
def rowStartCalculatorCode(self, row, baselabel):
if self.double_buffer:
first = self.height - 1
else:
first = 0
self.out()
self.comment_line("row %d" % row)
if self.double_buffer:
if row == first:
label = "%s_PAGELOOP" % (baselabel)
self.asm("ldx PARAM1")
self.asm("ldy #%d" % self.height)
self.label(label)
self.asm("lda HGRROWS_H1,x")
self.asm("pha")
self.asm("inx")
self.asm("dey")
self.asm("bne %s" % label)
self.asm("ldx PARAM1")
self.asm("pla")
cycles = 3
else:
self.asm("pla")
cycles = 4
if row == 0:
self.asm("ldx PARAM1")
cycles = 3
else:
if row == 0:
self.asm("ldx PARAM1")
cycles = 3
else:
cycles = 0
self.asm("lda HGRROWS_H1+%d,x" % row)
cycles += 4
cycles = 0
self.asm("lda HGRROWS_H1+%d,x" % row)
cycles += 4
if self.double_buffer:
# HGRSELECT must be set to $00 or $60. The eor then turns the high
# byte of page 1 into either page1 or page 2 by flipping the 5th
# and 6th bit
self.asm("eor HGRSELECT")
cycles += 3
self.asm("sta SCRATCH1")
self.asm("lda HGRROWS_L+%d,x" % row)
self.asm("sta SCRATCH0")
if row == first:
cycles += 3 + 4 + 3
if row == 0:
self.asm("ldy PARAM0")
self.asm("lda DIV%d_%d,y" % (self.screen.numShifts, self.screen.bitsPerPixel))
self.asm("sta PARAM2") # save the mod lookup; it doesn't change
@ -455,7 +438,7 @@ class Sprite(Listing):
else:
self.asm("ldy PARAM2")
cycles += 2
return cycles + 3 + 4 + 3;
return cycles;
def shiftStringRight(string, shift, bitsPerPixel, fillerBit):