[GUN]: added Loriciel West Phaser and Trojan Phazer lightgun modes, thx to @LilaQ

Co-authored-by: LilaQ <[email protected]>

Resolves #180, complete and fixes #125

Makefile.common

@@ -22,6 +22,7 @@ SOURCES_C := \
 	$(CORE_DIR)/cap32/asic.c \
 	$(CORE_DIR)/cap32/z80.c \
 	$(CORE_DIR)/cap32/kbdauto.c \
+	$(CORE_DIR)/cap32/lightgun/lightgun.c \
 	$(CORE_DIR)/cap32/lightgun/gunstick.c \
 	$(CORE_DIR)/cap32/lightgun/phaser.c \
 	$(CORE_DIR)/libretro/microui/microui.c \

cap32/cap32.c

@@ -1563,7 +1563,6 @@ int video_init (void)
 
    CPC.scr_bpp = retro_getGfxBpp();
    CPC.scr_density = 2 >> (CPC.scr_bpp >> 4);
-   printf("\n>>>>>>> b:%u d:%u\n", CPC.scr_bpp, CPC.scr_density);
    CPC.scr_style     = retro_getStyle();
    CPC.scr_bps       = retro_getGfxBps();
    CPC.scr_pos       = CPC.scr_base = retro_getScreenPtr();

cap32/lightgun/gunstick.c

@@ -69,58 +69,13 @@ static t_light light[2];
 #define GUNSTICK_TIMER         4
 
 
-static unsigned gunstick_luminance(uint32_t pixel)
-{
-   unsigned r, g, b;
-
-   switch (retro_video.depth) {
-      case DEPTH_16BPP:
-         r = (pixel >> 11) & 0x1F; r = (r << 3) | (r >> 2);
-         g = (pixel >> 5)  & 0x3F; g = (g << 2) | (g >> 4);
-         b = pixel         & 0x1F; b = (b << 3) | (b >> 2);
-         break;
-
-      case DEPTH_8BPP:
-         r = ((pixel >> 5) & 0x07) * 36;
-         g = ((pixel >> 2) & 0x07) * 36;
-         b = (pixel & 0x03) * 85;
-         break;
-
-      default:
-         r = (pixel >> 16) & 0xFF;
-         g = (pixel >> 8)  & 0xFF;
-         b = pixel         & 0xFF;
-         break;
-   }
-
-   return (299 * r) + (587 * g) + (114 * b);
-}
-
 void gunstick_reset(void)
 {
    memset(light, 0, sizeof(light));
 
    /* Guillermo Tell uses a light-yellow flash. Keep grey targets (Solo)
     * and allow a black sample followed by a flash (Mike Gunner). */
-   lightgun_cfg.threshold_color = gunstick_luminance(lightgun_cfg.luminance_color);
-}
-
-uint32_t _gunstick_get_screen(int x, int y)
-{
-   if ((unsigned)x >= (unsigned)EMULATION_SCREEN_WIDTH || 
-       (unsigned)y >= (unsigned)EMULATION_SCREEN_HEIGHT)
-      return 0;
-
-   int index = y * EMULATION_SCREEN_WIDTH + x - 1;
-
-   switch (retro_video.depth) {
-      case DEPTH_8BPP:
-         return ((uint8_t *)video_buffer)[index];
-      case DEPTH_16BPP:
-         return ((uint16_t *)video_buffer)[index];
-      default:
-         return video_buffer[index];
-   }
+   lightgun_cfg.threshold_color = lightgun_luminance(lightgun_cfg.luminance_color);
 }
 
 bool _gunstick_check(unsigned port)
@@ -134,8 +89,8 @@ bool _gunstick_check(unsigned port)
       gun[port].state = GUN_SSEND;
    }
 
-   gcolor = _gunstick_get_screen(light[port].x, light[port].y);
-   luminance = gunstick_luminance(gcolor);
+   gcolor = lightgun_get_screen(light[port].x, light[port].y);
+   luminance = lightgun_luminance(gcolor);
    #ifdef DEBUG_GUNSTICK
    printf("gunstick: 0x%X[0x%X] (%u,%u) [0x%X]\n", gcolor, luminance, light[port].x, light[port].y, lightgun_cfg.threshold_color);
    #endif

cap32/lightgun/lightgun.c

@@ -0,0 +1,101 @@
+/****************************************************************************
+ *  Caprice32 libretro port
+ *
+ *  Copyright David Colmenero - D_Skywalk (2019-2023)
+ *  - original header -
+ *  Pituka - Nintendo Wii/Gamecube Port
+ *  (c) Copyright 2008-2009 David Colmenero (aka D_Skywalk)
+ *
+ *  Redistribution and use of this code or any derivative works are permitted
+ *  provided that the following conditions are met:
+ *
+ *   - Redistributions may not be sold, nor may they be used in a commercial
+ *     product or activity.
+ *
+ *   - Redistributions that are modified from the original source must include the
+ *     complete source code, including the source code for all components used by a
+ *     binary built from the modified sources. However, as a special exception, the
+ *     source code distributed need not include anything that is normally distributed
+ *     (in either source or binary form) with the major components (compiler, kernel,
+ *     and so on) of the operating system on which the executable runs, unless that
+ *     component itself accompanies the executable.
+ *
+ *   - Redistributions must reproduce the above copyright notice, this list of
+ *     conditions and the following disclaimer in the documentation and/or other
+ *     materials provided with the distribution.
+ *
+ *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ *  POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************************/
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+
+#include <libretro.h>
+#include <libretro-core.h>
+
+#include "gfx/software.h"
+#include "gfx/video.h"
+#include "assets/assets.h"
+
+#include "cap32.h"
+#include "lightgun.h"
+#include "retro_gun.h"
+
+extern uint32_t * video_buffer;
+
+
+unsigned lightgun_luminance(uint32_t pixel)
+{
+   unsigned r, g, b;
+
+   switch (retro_video.depth) {
+      case DEPTH_16BPP:
+         r = (pixel >> 11) & 0x1F; r = (r << 3) | (r >> 2);
+         g = (pixel >> 5)  & 0x3F; g = (g << 2) | (g >> 4);
+         b = pixel         & 0x1F; b = (b << 3) | (b >> 2);
+         break;
+
+      case DEPTH_8BPP:
+         r = ((pixel >> 5) & 0x07) * 36;
+         g = ((pixel >> 2) & 0x07) * 36;
+         b = (pixel & 0x03) * 85;
+         break;
+
+      default:
+         r = (pixel >> 16) & 0xFF;
+         g = (pixel >> 8)  & 0xFF;
+         b = pixel         & 0xFF;
+         break;
+   }
+
+   return (299 * r) + (587 * g) + (114 * b);
+}
+
+unsigned int lightgun_get_screen(int x, int y)
+{
+   if ((unsigned)x >= (unsigned)EMULATION_SCREEN_WIDTH || 
+       (unsigned)y >= (unsigned)EMULATION_SCREEN_HEIGHT)
+      return 0;
+
+   int index = y * EMULATION_SCREEN_WIDTH + x - 1;
+
+   switch (retro_video.depth) {
+      case DEPTH_8BPP:
+         return ((uint8_t *)video_buffer)[index];
+      case DEPTH_16BPP:
+         return ((uint16_t *)video_buffer)[index];
+      default:
+         return video_buffer[index];
+   }
+}

cap32/lightgun/lightgun.h

@@ -54,4 +54,7 @@ typedef struct{
 extern t_lightgun gun[2];
 void ev_lightgun(unsigned port);
 
+unsigned lightgun_luminance(unsigned int pixel);
+unsigned int lightgun_get_screen(int x, int y);
+
 #endif

cap32/lightgun/phaser.c

@@ -31,13 +31,18 @@
 
 #include "cap32.h"
 #include "lightgun.h"
+#include "retro_gun.h"
 
 extern t_CPC CPC;
 extern t_CRTC CRTC;
 extern t_VDU VDU;
 
 
-#define PHASER_SCREEN_SHIFT 4
+#define PHASER_NONE              0xff
+#define PHASER_SCREEN_SHIFT      4
+#define WESTPHASER_FIRE_MASK     0x20  /* Bit 5 down (Joystick Fire 1) */
+#define WESTPHASER_HIT           0x01
+#define TROJAN_FIRE_MASK         0x10  /* Bit 4 down (Joystick Fire 2) */
 
 void phaser_emulator_update(void)
 {
@@ -61,7 +66,7 @@ void phaser_emulator_OUT()
    CRTC.registers[17] += 1;
 }
 
-void phaser_emulator_CRTC()
+static void phaser_latch(unsigned shift)
 {
    // If the trigger is pressed, it only updates it when the phazer receives light from the screen.
    if (gun[0].state != GUN_SHOOT)
@@ -70,7 +75,7 @@ void phaser_emulator_CRTC()
    unsigned int x = (CPC.scr_pos - CPC.scr_base) << CPC.scr_density;
    unsigned int y = VDU.scrln;
    
-   unsigned int address = CRTC.addr + CRTC.char_count + PHASER_SCREEN_SHIFT;
+   unsigned int address = CRTC.addr + CRTC.char_count + shift;
    
    if (gun[0].x >= x && gun[0].x < x + 16 && gun[0].y >= y && gun[0].y < y + 2)
    {
@@ -79,4 +84,71 @@ void phaser_emulator_CRTC()
    }
 }
 
-unsigned char phaser_emulator_IN(){ return 0xff; }
+void phaser_emulator_CRTC()
+{
+   phaser_latch(PHASER_SCREEN_SHIFT);
+}
+
+unsigned char phaser_emulator_IN(){ return PHASER_NONE; }
+
+/* The Plus AUX gun has a separate active-low trigger on joystick 1 fire 2.
+ * Unlike the expansion-port Magnum, it does not use writes to port FBFE. */
+unsigned char trojan_emulator_IN(void)
+{
+   if ((CPC.keyboard_line & 15) != 9)
+      return PHASER_NONE;
+
+   return gun[0].pressed ? (PHASER_NONE & ~TROJAN_FIRE_MASK) : PHASER_NONE;
+}
+
+void trojan_emulator_CRTC(void)
+{
+   phaser_latch(0);
+}
+
+
+/* Loriciel West Phaser - Implementación basada en rastreo del haz de electrones */
+unsigned char westphaser_emulator_IN(void)
+{
+   unsigned char value = PHASER_NONE;
+   int x, y;
+
+   /* The West Phaser connects to joystick port 1 (matrix line 9) */
+   if ((CPC.keyboard_line & 15) != 9)
+      return value;
+
+   /* On Fire we inject Bit 5 low (Joystick Fire 1) */
+   if (gun[0].pressed)
+      value &= ~WESTPHASER_FIRE_MASK;
+
+   /* If the gun is pointing off-screen, abort */
+   if (gun[0].x < 0 || gun[0].y < 0)
+      return value;
+
+   /* Exact electron beam tracking (Raster tracking)
+    * Get the X coordinate by subtracting the line base from the current memory position,
+    * adjusting by screen density. Y is provided directly by VDU.scrln. */
+   x = (CPC.scr_pos - CPC.scr_base) << CPC.scr_density;
+   y = VDU.scrln;
+
+   /* The Light sensor: Inject Bit 0 low (Joystick Up)
+    * The game times the start of the sensor response and then samples the
+    * subsequent scanlines. To simulate persistence, keep the signal active
+    * for the rest of each visible line AFTER the aim point (x > gun.x and y > gun.y),
+    * provided that the screen coordinate has a bright color. */
+   if (
+      VDU.flag_drawing &&
+      y > gun[0].y &&
+       x > gun[0].x &&
+       x < EMULATION_SCREEN_WIDTH
+   )
+   {
+      uint32_t color = lightgun_get_screen(gun[0].x, y);
+      if (lightgun_luminance(color) > lightgun_cfg.threshold_color)
+      {
+         value &= ~WESTPHASER_HIT;
+      }
+   }
+
+   return value;
+}

cap32/lightgun/phaser.h

@@ -43,4 +43,9 @@ unsigned char phaser_emulator_IN();
 void phaser_emulator_OUT();
 void phaser_emulator_CRTC();
 
+unsigned char trojan_emulator_IN(void);
+void trojan_emulator_CRTC(void);
+
+unsigned char westphaser_emulator_IN(void);
+
 #endif

libretro/libretro-core.c

@@ -470,8 +470,10 @@ static struct retro_core_option_v2_definition option_definitions[] = {
       "light_gun",
       {
          { "disabled", NULL },
-         { "phaser",   NULL },
-         { "gunstick", NULL },
+         { "phaser",   "Amstrad Magnum Phaser" },
+         { "gunstick", "Gun-Stick" },
+         { "west_phaser", "Loriciel West Phaser" },
+         { "trojan_phazer", "Trojan Phazer (CPC Plus / GX4000)" },
          { NULL, NULL },
       },
       "disabled"
@@ -730,7 +732,7 @@ static struct retro_variable variables[] = {
    },
    {
       "cap32_lightgun_input",
-      "Light Gun > Input; disabled|phaser|gunstick",
+      "Light Gun > Input; disabled|phaser|gunstick|west_phaser|trojan_phazer",
    },
    {
       "cap32_lightgun_show",
@@ -1009,6 +1011,8 @@ static void update_variables(void)
       lightgun_type val = LIGHTGUN_TYPE_NONE;
       if (strcmp(var.value, "phaser") == 0) val = LIGHTGUN_TYPE_PHASER;
       else if (strcmp(var.value, "gunstick") == 0) val = LIGHTGUN_TYPE_GUNSTICK;
+      else if (strcmp(var.value, "west_phaser") == 0) val = LIGHTGUN_TYPE_WEST_PHASER;
+      else if (strcmp(var.value, "trojan_phazer") == 0) val = LIGHTGUN_TYPE_TROJAN_PHAZER;
 
       if (lightgun_cfg.guntype != val) {
          lightgun_cfg.guntype = val;

libretro/retro_gun.c

@@ -90,6 +90,25 @@ void lightgun_prepare(lightgun_type guntype)
          CPC.gun_OUT = phaser_emulator_OUT;
          break;
 
+      case LIGHTGUN_TYPE_WEST_PHASER:
+         lightgun_cfg.gun_update = phaser_emulator_update;
+         CPC.gun_CRTC = NULL;
+         CPC.gun_IN = westphaser_emulator_IN;
+         CPC.gun_OUT = NULL;
+         break;
+
+      case LIGHTGUN_TYPE_TROJAN_PHAZER:
+         if (retro_computer_cfg.model != CPC_MODEL_PLUS) {
+            retro_message("Trojan lightgun is for CPC6128+");
+            break;
+         }
+
+         lightgun_cfg.gun_update = phaser_emulator_update;
+         CPC.gun_CRTC = trojan_emulator_CRTC;
+         CPC.gun_IN = trojan_emulator_IN;
+         CPC.gun_OUT = NULL;
+         break;
+
       default:
          lightgun_cfg.gun_draw = NULL;
          lightgun_cfg.gun_update = NULL;

libretro/retro_gun.h

@@ -41,8 +41,10 @@
 typedef enum {
     LIGHTGUN_TYPE_UNCONFIGURED,
     LIGHTGUN_TYPE_NONE,
-    LIGHTGUN_TYPE_PHASER,
     LIGHTGUN_TYPE_GUNSTICK,
+    LIGHTGUN_TYPE_PHASER,
+    LIGHTGUN_TYPE_TROJAN_PHAZER,
+    LIGHTGUN_TYPE_WEST_PHASER,
 } lightgun_type;
 
 typedef struct