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More VGA tests

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This commit is contained in:
Jeff Parsons 2015-07-05 11:38:30 -07:00
commit 69d4893ec6
2 changed files with 191 additions and 5 deletions
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20
modules/pcjs/lib/video.js
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@ -3589,10 +3589,10 @@ Video.prototype.getCardColors = function(nBitsPerPixel)
if (nBitsPerPixel == 8) {
/*
* The card must be a VGA, and it's using an (8bpp) mode that bypasses the ATC, so we need
* to pull RGB data exclusively from the 256-entry DAC; each entry contains 6-bit red, green,
* and blue values packed into bits 0-5, 6-11, and 12-17, respectively, each of which we
* effectively shift left 2 bits: a crude 6-to-8-bit color conversion.
* The card must be a VGA, and it's using an (8bpp) mode that bypasses the ATC, so we need to pull
* RGB data exclusively from the 256-entry DAC; each entry contains 6-bit red, green, and blue values
* packed into bits 0-5, 6-11, and 12-17, respectively, each of which we effectively shift left 2 bits:
* a crude 6-to-8-bit color conversion.
*/
for (i = 0; i < 256; i++) {
dw = aDAC[i] || 0;
@ -3605,12 +3605,22 @@ Video.prototype.getCardColors = function(nBitsPerPixel)
} else {
/*
* We need to pull RGB data from the ATC; moreover, if the ATC hasn't been initialized yet,
* we go with a default EGA-compatible 16-color palette.
* we go with a default EGA-compatible 16-color palette. We'll also use the DAC if there is one
* (ie, this is actually a VGA) and it appears to be initialized (ie, the VGA BIOS has been run).
*/
var fDAC = (aDAC && aDAC[255]);
aRegs = (card.regATCData[15] != null? card.regATCData : Video.aEGAPalDef);
for (i = 0; i < 16; i++) {
b = aRegs[i] & Card.ATC.PALETTE.MASK;
/*
* If the DAC is valid, we need to supplement the 6 bits of each ATC palette entry with the values
* for bits 6 and 7 from the ATC COLORSEL register (and overwrite bits 4 and 5 if ATC.MODE.COLORSEL_ALL
* is set as well).
*
* The only reason the DAC wouldn't be valid is if 1) we're trying to display an image before the machine
* and its BIOS have had a chance to initialize the DAC (because we don't preset it to anything, although
* perhaps we should), or 2) this is an EGA, which doesn't have a DAC.
*/
if (fDAC) {
b |= (card.regATCData[Card.ATC.COLORSEL.INDX] & (Card.ATC.COLORSEL.DAC_BIT7 | Card.ATC.COLORSEL.DAC_BIT6)) << 4;
if (card.regATCData[Card.ATC.MODE.INDX] & Card.ATC.MODE.COLORSEL_ALL) {