src/add-ons/accelerants/ati/mach64_cursor.cpp

   1 /*
   2         Copyright 2009 Haiku, Inc.  All rights reserved.
   3         Distributed under the terms of the MIT license.
   4
   5         Authors:
   6         Gerald Zajac 2009
   7 */
   8
   9
  10 #include "accelerant.h"
  11 #include "mach64.h"
  12
  13 #include <string.h>
  14
  15
  16
  17 void
  18 Mach64_ShowCursor(bool bShow)
  19 {
  20         // Turn cursor on/off.
  21
  22         OUTREGM(GEN_TEST_CNTL, bShow ? HWCURSOR_ENABLE : 0, HWCURSOR_ENABLE);
  23 }
  24
  25
  26 void
  27 Mach64_SetCursorPosition(int x, int y)
  28 {
  29         SharedInfo& si = *gInfo.sharedInfo;
  30
  31         // xOffset & yOffset are used for displaying partial cursors on screen edges.
  32
  33         uint8 xOffset = 0;
  34         uint8 yOffset = 0;
  35
  36         if (x < 0) {
  37                 xOffset = -x;
  38                 x = 0;
  39         }
  40
  41         if (y < 0) {
  42                 yOffset = -y;
  43                 y = 0;
  44         }
  45
  46         OUTREG(CUR_OFFSET, (si.cursorOffset >> 3) + (yOffset << 1));
  47         OUTREG(CUR_HORZ_VERT_OFF, (yOffset << 16) | xOffset);
  48         OUTREG(CUR_HORZ_VERT_POSN, (y << 16) | x);
  49 }
  50
  51
  52 bool
  53 Mach64_LoadCursorImage(int width, int height, uint8* andMask, uint8* xorMask)
  54 {
  55         SharedInfo& si = *gInfo.sharedInfo;
  56
  57         if (andMask == NULL || xorMask == NULL)
  58                 return false;
  59
  60         uint16* fbCursor = (uint16*)((addr_t)si.videoMemAddr + si.cursorOffset);
  61
  62         // Initialize the hardware cursor as completely transparent.
  63
  64         memset(fbCursor, 0xaa, CURSOR_BYTES);
  65
  66         // Now load the AND & XOR masks for the cursor image into the cursor
  67         // buffer.  Note that a particular bit in these masks will have the
  68         // following effect upon the corresponding cursor pixel:
  69         //      AND  XOR        Result
  70         //       0    0          White pixel
  71         //       0    1          Black pixel
  72         //       1    0          Screen color (for transparency)
  73         //       1    1          Reverse screen color to black or white
  74
  75         for (int row = 0; row < height; row++) {
  76                 for (int colByte = 0; colByte < width / 8; colByte++) {
  77                         // Convert the 8 bit AND and XOR masks into a 16 bit mask containing
  78                         // pairs of the bits from the AND and XOR maks.
  79
  80                         uint8 andBits = *andMask++;
  81                         uint8 xorBits = *xorMask++;
  82                         uint16 cursorBits = 0;
  83
  84                         for (int j = 0; j < 8; j++) {
  85                                 cursorBits <<= 2;
  86                                 cursorBits |= ((andBits & 0x01) << 1);
  87                                 cursorBits |= (xorBits & 0x01);
  88                                 andBits >>= 1;
  89                                 xorBits >>= 1;
  90                         }
  91
  92                         fbCursor[row * 8 + colByte] = cursorBits;
  93                 }
  94         }
  95
  96         // Set the cursor colors which are white background and black foreground.
  97
  98         OUTREG(CUR_CLR0, ~0);
  99         OUTREG(CUR_CLR1, 0);
 100
 101         return true;
 102 }