Apply special remapping to the NSO N64 controller when reported as Pro Controller.

Author: Banz99

mc_mitm/source/controllers/forced_pro_controller.cpp

@@ -18,8 +18,30 @@
 
 namespace ams::controller {
 
+    namespace {
+
+        bool ApplyN64Remapping(SwitchButtonData *buttons) {
+            bool alternatescheme = buttons->Y; //C-Up
+            buttons->Y = buttons->ZR; //C-Down -> Y
+            buttons->ZR = buttons->lstick_press; //ZR -> ZR
+            buttons->lstick_press = 0;
+            if (alternatescheme) {
+                buttons->lstick_press = buttons->L; //L -> LEFT STICK PRESS
+                buttons->rstick_press = buttons->R; //R -> RIGHT STICK PRESS
+                buttons->L = 0;
+                buttons->R = 0;
+            }
+            return alternatescheme;
+        }
+
+    }
+
     ForcedProController::ForcedProController(const bluetooth::Address *address, HardwareID id)
-    : SwitchController(address, id) {}
+    : SwitchController(address, id)
+    , m_is_n64_controller(false) {
+        if (m_id.pid == 0x2019)
+            m_is_n64_controller = true;
+    }
 
 
     Result ForcedProController::HandleDataReportEvent(const bluetooth::HidReportEventInfo *event_info) {
@@ -57,6 +79,31 @@ namespace ams::controller {
                             std::memcpy(response->data.serial_flash_read.data, data, sizeof(data));
                         }
                     }
+                    else if (m_is_n64_controller) {
+                        switch (response->data.serial_flash_read.address) {
+                            case 0x603d: //Factory stick calibration
+                                memcpy(&response->data.serial_flash_read.data[9], &response->data.serial_flash_read.data[3], 3); //Swap calibration triplets for the right stick (https://github.com/dekuNukem/Nintendo_Switch_Reverse_Engineering/blob/master/spi_flash_notes.md)
+                                memcpy(&m_n64_calibrated_stick_zero, &response->data.serial_flash_read.data[3], 3);
+                                memcpy(&response->data.serial_flash_read.data[12], &response->data.serial_flash_read.data[6], 3);
+                                memcpy(&response->data.serial_flash_read.data[15], &response->data.serial_flash_read.data[0], 3);
+                                break;
+                            case 0x8010: //User stick calibration
+                                if (response->data.serial_flash_read.data[0] != 0xFF && response->data.serial_flash_read.data[1] != 0xFF) {
+                                    memcpy(&response->data.serial_flash_read.data[11], &response->data.serial_flash_read.data[0], 2); //Copy magic numbers that signal the presence of a user calibration
+                                    memcpy(&response->data.serial_flash_read.data[13], &response->data.serial_flash_read.data[5], 3); //Swap calibration triplets for the right stick
+                                    memcpy(&m_n64_calibrated_stick_zero, &response->data.serial_flash_read.data[5], 3);
+                                    memcpy(&response->data.serial_flash_read.data[16], &response->data.serial_flash_read.data[8], 3);
+                                    memcpy(&response->data.serial_flash_read.data[19], &response->data.serial_flash_read.data[2], 3);
+                                }
+                                break;
+                            case 0x6080: //Left stick parameters (always read first) (first 6 bytes are 6-Axis Horizontal Offsets which we don't need)
+                                memcpy(&m_n64_left_stick_param, &response->data.serial_flash_read.data[6],sizeof(SwitchAnalogStickParameters));
+                                break;
+                            case 0x6098: //Right stick parameters (always read after the left ones)
+                                memcpy(&response->data.serial_flash_read.data, &m_n64_left_stick_param, sizeof(SwitchAnalogStickParameters));
+                                break;
+                        }
+                    }
                     break;
                 case HidCommand_GetDeviceInfo:
                     response->data.get_device_info.type = 0x03;
@@ -65,6 +112,14 @@ namespace ams::controller {
             }
         }
 
+        if (m_is_n64_controller) {
+            if (ApplyN64Remapping(&input_report->buttons)) {
+                input_report->right_stick.SetData(input_report->left_stick.GetX(), input_report->left_stick.GetY());
+                memcpy(&input_report->left_stick.m_xy, &m_n64_calibrated_stick_zero, 3);
+            }
+            else memcpy(&input_report->right_stick.m_xy, &m_n64_calibrated_stick_zero, 3);
+        }
+
         this->ApplyButtonCombos(&input_report->buttons);
 
         return bluetooth::hid::report::WriteHidDataReport(m_address, &m_input_report);

mc_mitm/source/controllers/forced_pro_controller.hpp

@@ -26,6 +26,10 @@ namespace ams::controller {
 
             Result HandleDataReportEvent(const bluetooth::HidReportEventInfo *event_info);
             Result HandleOutputDataReport(const bluetooth::HidReport *report);
+        private:
+            bool m_is_n64_controller;
+            SwitchAnalogStickParameters m_n64_left_stick_param;
+            uint8_t m_n64_calibrated_stick_zero[3];
 
     };