complete wheel support

6 files changed, 124 insertions, 27 deletions

diff --git a/dosmain.c b/dosmain.c
index ee6389c..c35975e 100644
--- a/dosmain.c
+++ b/dosmain.c
@@ -28,6 +28,24 @@
 #include "vbox.h"
 #include "dostsr.h"
 
+static int set_wheel(LPTSRDATA data, bool enable)
+{
+	printf("Setting wheel support to %s\n", enable ? "enabled" : "disabled");
+	data->usewheel = enable;
+
+	if (data->usewheel) {
+		// Do a quick check for a mouse wheel here.
+		// The TSR will do its own check when it is reset anyway
+		if (data->haswheel = ps2m_detect_wheel()) {
+			printf("Wheel mouse found and enabled\n");
+		}
+	} else {
+		data->haswheel = false;
+	}
+
+	return 0;
+}
+
 #if USE_VIRTUALBOX
 static int set_integration(LPTSRDATA data, bool enable)
 {
@@ -99,15 +117,7 @@ static int configure_driver(LPTSRDATA data)
 	}
 
 	// Let's utilize the wheel by default
-	data->usewheel = true;
-
-	if (data->usewheel) {
-		// Do a quick check for a mouse wheel here.
-		// The TSR will do its own check when it is reset anyway
-		if (data->haswheel = ps2m_detect_wheel()) {
-			printf("Wheel mouse found and enabled\n");
-		}
-	}
+	set_wheel(data, true);
 
 #if USE_VIRTUALBOX
 	// Assume initially that we want integration and host cursor
@@ -232,6 +242,7 @@ static void print_help(void)
 	    "Supported actions:\n"
 	    "\tinstall           install the driver (default)\n"
 	    "\tuninstall         uninstall the driver from memory\n"
+	    "\twheel <ON|OFF>    enable/disable wheel API support\n"
 #if USE_VIRTUALBOX
 	    "\tinteg <ON|OFF>    enable/disable virtualbox integration\n"
 	    "\thostcur <ON|OFF>  enable/disable mouse cursor rendering in host\n"
@@ -289,6 +300,17 @@ int main(int argc, const char *argv[])
 			return EXIT_FAILURE;
 		}
 		return uninstall_driver(data);
+	} else if (stricmp(argv[argi], "wheel") == 0) {
+		bool enable = true;
+
+		if (!data) return driver_not_found();
+
+		argi++;
+		if (argi < argc) {
+			if (is_false(argv[argi])) enable = false;
+		}
+
+		return set_wheel(data, enable);
 #if USE_VIRTUALBOX
 	} else if (stricmp(argv[argi], "integ") == 0) {
 		bool enable = true;
@@ -311,6 +333,9 @@ int main(int argc, const char *argv[])
 			if (is_false(argv[argi])) enable = false;
 		}
 
+		// Reset before changing this to ensure the cursor is not drawn
+		int33_reset();
+
 		return set_host_cursor(data, enable);
 #endif
 	} else if (stricmp(argv[argi], "reset") == 0) {
diff --git a/dostsr.c b/dostsr.c
index 57ec089..7d881e2 100644
--- a/dostsr.c
+++ b/dostsr.c
@@ -384,7 +384,6 @@ static void load_cursor(void)
 /** Refreshes the information about the current video mode. */
 static void refresh_video_info(void)
 {
-	uint8_t screen_columns = bda_get_num_columns();
 	uint8_t mode = bda_get_video_mode() & ~0x80;
 	bool mode_change = mode != data.screen_mode;
 
@@ -396,7 +395,9 @@ static void refresh_video_info(void)
 	dlog_print("Current video mode=");
 	dlog_printx(mode);
 	dlog_print(" with cols=");
-	dlog_printd(screen_columns);
+	dlog_printd(bda_get_num_columns());
+	dlog_print(" lastrow=");
+	dlog_printd(bda_get_last_row());
 	dlog_endline();
 
 	data.screen_mode = mode;
@@ -412,8 +413,8 @@ static void refresh_video_info(void)
 	case 2:
 	case 3: // CGA text modes with 25 rows and variable columns
 	case 7: // MDA Mono text mode
-		data.screen_max.x = (screen_columns * 8) - 1;
-		data.screen_max.y = (25 * 8) - 1;
+		data.screen_max.x = (bda_get_num_columns() * 8) - 1;
+		data.screen_max.y = (                   25 * 8) - 1;
 		break;
 
 	case 4:
@@ -736,6 +737,7 @@ static void reset_mouse_state()
 		data.button[i].released.last.x = 0;
 		data.button[i].released.last.y = 0;
 	}
+	data.wheel_delta = 0;
 	data.cursor_visible = false;
 	data.cursor_pos.x = 0;
 	data.cursor_pos.y = 0;
@@ -743,6 +745,16 @@ static void reset_mouse_state()
 	bzero(data.cursor_prev_graphic, sizeof(data.cursor_prev_graphic));
 }
 
+static void return_clear_wheel_counter(union INTPACK __far *r)
+{
+	r->x.cx = data.wheel_last.x;
+	r->x.dx = data.wheel_last.y;
+	r->x.bx = data.wheel_delta;
+	data.wheel_last.x = 0;
+	data.wheel_last.y = 0;
+	data.wheel_delta = 0;
+}
+
 static void return_clear_button_counter(union INTPACK __far *r, struct buttoncounter *c)
 {
 	r->x.cx = c->last.x;
@@ -778,6 +790,10 @@ static void int33_handler(union INTPACK r)
 		r.x.cx = data.pos.x;
 		r.x.dx = data.pos.y;
 		r.x.bx = data.buttons;
+		if (data.haswheel) {
+			r.h.bh = data.wheel_delta;
+			data.wheel_delta = 0;
+		}
 		break;
 	case INT33_SET_MOUSE_POSITION:
 		data.pos.x = r.x.cx;
@@ -792,11 +808,30 @@ static void int33_handler(union INTPACK r)
 		break;
 	case INT33_GET_BUTTON_PRESSED_COUNTER:
 		r.x.ax = data.buttons;
-		return_clear_button_counter(&r, &data.button[MIN(r.x.bx, NUM_BUTTONS - 1)].pressed);
+		if (data.haswheel) {
+			r.h.bh = data.wheel_delta;
+		}
+		if (data.haswheel && r.x.bx == -1) {
+			// Wheel information
+			return_clear_wheel_counter(&r);
+		} else {
+			// Regular button information
+			int btn = MIN(r.x.bx, NUM_BUTTONS - 1);
+			return_clear_button_counter(&r, &data.button[btn].pressed);
+		}
 		break;
 	case INT33_GET_BUTTON_RELEASED_COUNTER:
 		r.x.ax = data.buttons;
-		return_clear_button_counter(&r, &data.button[MIN(r.x.bx, NUM_BUTTONS - 1)].released);
+		if (data.haswheel) {
+			r.h.bh = data.wheel_delta;
+		}
+		if (data.haswheel && r.x.bx == -1) {
+			// Wheel information
+			return_clear_wheel_counter(&r);
+		} else {
+			int btn = MIN(r.x.bx, NUM_BUTTONS - 1);
+			return_clear_button_counter(&r, &data.button[btn].released);
+		}
 		break;
 	case INT33_SET_HORIZONTAL_WINDOW:
 		dlog_print("Mouse set horizontal window [");
@@ -937,6 +972,11 @@ static void int33_handler(union INTPACK r)
 		r.x.cx = data.max.x;
 		r.x.dx = data.max.y;
 		break;
+	case INT33_GET_CAPABILITIES:
+		r.x.ax = INT33_WHEEL_API_MAGIC; // Driver supports wheel API
+		r.x.bx = 0;
+		r.x.cx = data.haswheel ? INT33_CAPABILITY_MOUSE_API : 0;
+		break;
 	case INT33_GET_TSR_DATA:
 		dlog_puts("Get TSR data");
 		r.x.es = FP_SEG(&data);
diff --git a/dostsr.h b/dostsr.h
index b9a5b73..e64c93e 100644
--- a/dostsr.h
+++ b/dostsr.h
@@ -114,6 +114,10 @@ typedef struct tsrdata {
 			uint16_t count;
 		} pressed, released;
 	} button[NUM_BUTTONS];
+	/** Total delta movement of the wheel since the last wheel report. */
+	int16_t wheel_delta;
+	/** Last position where the wheel was moved. */
+	struct point wheel_last;
 
 	// Cursor information
 	/** Whether the cursor is currently displayed or not. */
diff --git a/int10vga.h b/int10vga.h
index e254e3f..a2a20a0 100644
--- a/int10vga.h
+++ b/int10vga.h
@@ -38,6 +38,7 @@ static inline uint8_t bda_get_byte(unsigned int offset) {
 #define bda_get_num_columns()     bda_get_word(0x4a)
 #define bda_get_video_page_size() bda_get_word(0x4c)
 #define bda_get_cur_video_page()  bda_get_word(0x62)
+#define bda_get_last_row()        bda_get_byte(0x84)
 
 #define bda_get_tick_count()      bda_get_dword(0x6c)
 #define bda_get_tick_count_lo()   bda_get_word(0x6c)
diff --git a/int33.h b/int33.h
index f97ba21..44f61f9 100644
--- a/int33.h
+++ b/int33.h
@@ -129,16 +129,22 @@ enum INT33_API {
 	/** Gets the current window coordinates (set by INT33_SET_HORIZONTAL_WINDOW).
 	 *  @return ax min_x, bx min_y, cx max_x, d max_y. */
 	INT33_GET_WINDOW = 0x31,
-};
 
-enum INT33_API_INTERNAL {
+	// Wheel API Extensions:
+	INT33_GET_CAPABILITIES = 0x11,
+
+	// Our internal API functions:
+	/** Obtains a pointer to the driver's data. */
 	INT33_GET_TSR_DATA = 0x7f
 };
 
-enum {
-	INT33_MOUSE_FOUND = 0xFFFF
+enum INT33_CAPABILITY_BITS {
+	INT33_CAPABILITY_MOUSE_API = 1 << 0
 };
 
+#define INT33_WHEEL_API_MAGIC 'WM'
+#define INT33_MOUSE_FOUND 0xFFFF
+
 enum INT33_MOUSE_TYPE {
 	INT33_MOUSE_TYPE_BUS = 1,
 	INT33_MOUSE_TYPE_SERIAL = 2,
@@ -181,14 +187,14 @@ static uint16_t int33_reset(void);
 	"int 0x33" \
 	__value [ax]
 
-static void int33_set_horizontal_window(uint16_t min, uint16_t max);
+static void int33_set_horizontal_window(int16_t min, int16_t max);
 #pragma aux int33_set_horizontal_window = \
 	"mov ax, 0x7" \
 	"int 0x33" \
 	__parm [cx] [dx] \
 	__modify [ax]
 
-static void int33_set_vertical_window(uint16_t min, uint16_t max);
+static void int33_set_vertical_window(int16_t min, int16_t max);
 #pragma aux int33_set_vertical_window = \
 	"mov ax, 0x8" \
 	"int 0x33" \
@@ -202,4 +208,17 @@ static void int33_set_event_handler(uint16_t event_mask, void (__far *handler)()
 	__parm [cx] [es dx] \
 	__modify [ax]
 
+static uint16_t int33_get_driver_version(void);
+#pragma aux int33_get_driver_version = \
+	"mov bx, 0" \
+	"mov ax, 0x24" \
+	"int 0x33" \
+	"cmp ax, -1" \
+	"jne end" \
+	"error:" \
+	"mov bx, 0" \
+	"end:" \
+	__value [bx] \
+	__modify [ax bx cx dx]
+
 #endif
diff --git a/w16mouse.c b/w16mouse.c
index 2faefbf..f4c16a9 100644
--- a/w16mouse.c
+++ b/w16mouse.c
@@ -116,13 +116,18 @@ static void FAR int33_mouse_callback(uint16_t events, uint16_t buttons, int16_t
  * The initialization routine should check whether a mouse exists.
  * @return nonzero value indicates a mouse exists.
  */
-#pragma off (unreferenced);
+#pragma off (unreferenced)
 BOOL FAR PASCAL LibMain(HINSTANCE hInstance, WORD wDataSegment,
                         WORD wHeapSize, LPSTR lpszCmdLine)
-#pragma pop (unreferenced);
+#pragma pop (unreferenced)
 {
-	// We are not going to bother checking whether the int33 driver exists
-	// and just assume it does.
+	uint16_t version = int33_get_driver_version();
+
+	// For now we just check for the presence of any int33 driver version
+	if (version <= 0) {
+		// This will cause a "can't load .drv" message from Windows
+		return 0;
+	}
 
 	return 1;
 }
@@ -149,6 +154,10 @@ VOID FAR PASCAL Enable(LPFN_MOUSEEVENT lpEventProc)
 	if (!enabled) {
 		int33_reset();
 
+		// Since the mouse driver will likely not know the Windows resolution,
+		// let's manually set up a large window of coordinates so as to have
+		// as much precision as possible.
+		// We use 0x7FFF instead of 0xFFFF because this parameter is officially a signed value.
 		int33_set_horizontal_window(0, 0x7FFF);
 		int33_set_vertical_window(0, 0x7FFF);
 
@@ -162,8 +171,7 @@ VOID FAR PASCAL Enable(LPFN_MOUSEEVENT lpEventProc)
 VOID FAR PASCAL Disable(VOID)
 {
 	if (enabled) {
-		int33_reset();
-
+		int33_reset(); // This removes our handler and removes all other settings
 		enabled = false;
 	}
 }