Ticket #4847: wacom.diff

haiku/src/add-ons/input_server/devices/

@@ -292 +292 @@
             break;
         }
         case DEVICE_INTUOS:
+            // Modifications to correct (original) Intuos functioning in the following section.
+            // The critical point is that data[6] is used to signal use of the eraser,
+            // as well as being the high bits of pressure.  The indication is only valid
+            // when the pen is *not* in contact with the tablet, so it must be retained
+            // from the pre-touch state while the pen is in contact.
+            // (Always) while not in contact:
+            //  If the pen end is lowermost data[6] = 1;
+            //  If the eraser end is down data[6] = 0, and pressure is strictly 0
+            // data[9] (top 5 bits: 0x70..0xd0) indicates height above the tablet;
+            // this is used to prevent pressure jitter giving false eraser state.
         case DEVICE_INTUOS3:
         case DEVICE_CINTIQ:
             if ((data[0] == 0x02) && !(((data[1] >> 5) & 0x03) == 0x02)) {
@@ -319 +329 @@
                     pressure = 0.0;
                     eraser = 0;
                 } else {
-//                  eraser = (data[1] & 0x20); // eraser is een tool-id
+//                  eraser = (data[1] & 0x20); // eraser is in tool-id -- actually not!
 //                  firstButton = (pressureData > 0) && data[9] <= 0x68;// > 180);
 //                  firstButton = (pressureData > 180);
-                    firstButton = (data[6] > 0);
+//                  firstButton = (data[6] > 2);
+                    // This should be OK for all tablets(?):
+                    // For Intuos it MUST be >1, but '>1' still gets false actuations (shaking)
+                    firstButton = (data[6] > 2);
                     secondButton = (data[1] & 0x02);
                     thirdButton = (data[1] & 0x04);
-                    hasContact = (data[1] & 0x40);
-                    // convert tilt (-128 ... 127)
-//                  int8 tiltDataX = ((data[7] & 0x3f) << 2) | ((data[8] & 0x80) >> 6);
+                    hasContact = (data[1] & 0x40);  // is this meaningful? (always true on Intuos)
+                    if (fDeviceMode == DEVICE_INTUOS) { // test perhaps superfluous?
+                        eraser = fEraser;   // keep established value unless not touching pad
+                        // Eraser state only valid when away from surface
+                        if (data[6] <= 1 && data[9] > 0x80) {   // not touching tablet
+                            if (!pressureData) eraser = 1;  // strictly 0 means eraser
+                            else if (pressureData > 6) eraser = 0;  // avoid slop
+                        }
+                    }
+                    // Get raw tilt values (0..54..127):
                     int8 tiltDataX = ((data[7] & 0x3f) << 1) | ((data[8] & 0x80) >> 7);
                     int8 tiltDataY = data[8] & 0x7f;
-//                  int8 tiltDataY = 0;
                     // convert to floats
                     tiltX = (float)(tiltDataX - 64) / 64.0;
                     tiltY = (float)(tiltDataY - 64) / 64.0;