implement graphic cursor for CGA modes, wheel mouse detection, int2f hooking, simplify w16 driver

1 files changed, 30 insertions, 1 deletions

diff --git a/int10vga.h b/int10vga.h
index f3e0a07..e254e3f 100644
--- a/int10vga.h
+++ b/int10vga.h
@@ -5,6 +5,7 @@
 
 #define BIOS_DATA_AREA_SEGMENT 0x40
 
+// TODO Assuming screenwidth, videopage on ss rather than using far
 static uint8_t int10_get_video_mode(uint8_t *screenwidth, uint8_t *videopage);
 #pragma aux int10_get_video_mode = \
 	"mov al, 0" \
@@ -16,6 +17,11 @@ static uint8_t int10_get_video_mode(uint8_t *screenwidth, uint8_t *videopage);
 	__value [al] \
 	__modify [ax bh]
 
+static inline uint32_t bda_get_dword(unsigned int offset) {
+	uint32_t __far *p = MK_FP(BIOS_DATA_AREA_SEGMENT, offset);
+	return *p;
+}
+
 static inline uint16_t bda_get_word(unsigned int offset) {
 	uint16_t __far *p = MK_FP(BIOS_DATA_AREA_SEGMENT, offset);
 	return *p;
@@ -26,10 +32,14 @@ static inline uint8_t bda_get_byte(unsigned int offset) {
 	return *p;
 }
 
+#define bda_get_ebda_segment()    bda_get_word(0x0e)
+
 #define bda_get_video_mode()      bda_get_byte(0x49)
 #define bda_get_num_columns()     bda_get_word(0x4a)
 #define bda_get_video_page_size() bda_get_word(0x4c)
-//#define bda_get_tick_count()      bda_get_dword(0x6c)
+#define bda_get_cur_video_page()  bda_get_word(0x62)
+
+#define bda_get_tick_count()      bda_get_dword(0x6c)
 #define bda_get_tick_count_lo()   bda_get_word(0x6c)
 
 static inline uint16_t __far * get_video_char(uint8_t page, unsigned int x, unsigned int y)
@@ -38,4 +48,23 @@ static inline uint16_t __far * get_video_char(uint8_t page, unsigned int x, unsi
 	                     + ((y * bda_get_num_columns()) + x) * 2);
 }
 
+static inline uint8_t __far * get_video_scanline(uint8_t mode, uint8_t page, unsigned int y)
+{
+	switch (mode) {
+	case 4:
+	case 5:
+	case 6: // CGA modes
+		// Scalines are 80 bytes long, however they are interleaved.
+		// Even numbered scanlines begin at 0, odd lines begin at 0x2000.
+		// So offset by y%2 * 0x2000.
+		return MK_FP(0xB800, (page * bda_get_video_page_size())
+		                      + ((y/2) * 80) + (y%2) * 0x2000);
+
+	default:
+		return 0;
+	}
+}
+
+
+
 #endif