BLuRry wrote:
I've been trying to figure out a way to render hires to a double-hires bitmap, but also taking into account the odd combinations of color frindges. See the following example paraphrased from Sather's book below: 1 hgr2:for a=1 to 3:read c:hcolor=c:read n:for b=1 to n: read x:hplot x,0 to x,191:next b,a:data 4,3,0,21,42,7,9,62,83,104,125,159,180,220,247,279,3,10,20,41,105,126,161,182,206,233,262,263 I know why it happens, I'm just trying to find the most efficient way to programatically explain this behavior. Any takers?
I've never seen a program explain anything. ;-) If you mean how can you get exactly the same behavior from a DHR display that you see from an HGR display, that's pretty straightforward. The HGR display is a subset of the DHR display where each HGR pixel is represented by two DHR pixels. Instead of thinking about colors and "4-bit color pixels", just think about the video bits shifted out and the timing of their edges, as if it were a monochrome display. NTSC aliasing will take care of creating all the colors--and their fringes. For example, each of the seven low bits of an HGR line translates to two consecutive bits in the DHR line, and the high bit shifts their position in the DHR line by one DHR bit position. -michael NadaNet networking for Apple II computers! Home page: http://members.aol.com/MJMahon/ "The wastebasket is our most important design tool--and it's seriously underused."