Add wheel event on Web

2 files changed, 52 insertions, 10 deletions

diff --git a/index.htm b/index.htm
index 437b932..ada10e2 100644
--- a/index.htm
+++ b/index.htm
@@ -141,6 +141,13 @@
                 this.program.exports.js_keyup(ev.key, ev.mod);
               },
 
+              wheel : (ev) => {
+                if (this.program === undefined)
+                  return;
+
+                this.program.exports.js_wheel(ev.x * -0.01, ev.y * -0.01);
+              },
+
               paste : (ev) => {
                 if (this.program === undefined)
                   return;
@@ -559,6 +566,18 @@
           });
         });
 
+        window.addEventListener("wheel", (ev) => {
+          ev.preventDefault();
+          if (!sound_ready)
+            return;
+
+          sound_node.port.postMessage({
+            id : "wheel",
+            x  : ev.deltaX,
+            y  : ev.deltaY,
+          });
+        });
+
         window.addEventListener("paste", (ev) => {
           ev.preventDefault();
           if (!sound_ready)
diff --git a/reduced_system_layer.c b/reduced_system_layer.c
index 8370c46..4043f58 100644
--- a/reduced_system_layer.c
+++ b/reduced_system_layer.c
@@ -239,6 +239,10 @@ i32 main(i32 argc, c8 **argv);
 #define DROP_FILES_BUFFER_SIZE (20 * 1024 * 1024)
 #endif
 
+#ifndef MOUSE_WHEEL_FACTOR
+#define MOUSE_WHEEL_FACTOR (1.0)
+#endif
+
 //  ================================================================
 //
 //    Basic declarations
@@ -532,8 +536,8 @@ typedef struct {
   i32 cursor_y;
   i32 cursor_dx;
   i32 cursor_dy;
-  i64 wheel_dx;
-  i64 wheel_dy;
+  f64 wheel_dx;
+  f64 wheel_dy;
   i64 num_sound_samples_elapsed;
 
   i64        num_drop_files;
@@ -1678,10 +1682,10 @@ i32 p_handle_events(void) {
             g_platform.key_down   [BUTTON_RIGHT] = 1;
             g_platform.key_pressed[BUTTON_RIGHT] = 1;
             break;
-          case Button4:     ++g_platform.wheel_dy; break;
-          case Button5:     --g_platform.wheel_dy; break;
-          case Button5 + 1: --g_platform.wheel_dx; break;
-          case Button5 + 2: ++g_platform.wheel_dx; break;
+          case Button4:     g_platform.wheel_dy += MOUSE_WHEEL_FACTOR; break;
+          case Button5:     g_platform.wheel_dy -= MOUSE_WHEEL_FACTOR; break;
+          case Button5 + 1: g_platform.wheel_dx -= MOUSE_WHEEL_FACTOR; break;
+          case Button5 + 2: g_platform.wheel_dx += MOUSE_WHEEL_FACTOR; break;
           default:;
         }
         if (!requested_clipboard) {
@@ -2175,6 +2179,10 @@ static i32 _frame_width    = 0;
 static i32 _frame_height   = 0;
 static i32 _num_events     = 0;
 static i32 _input_size     = 0;
+static i32 _cursor_dx      = 0;
+static i32 _cursor_dy      = 0;
+static f64 _wheel_dx       = 0;
+static f64 _wheel_dy       = 0;
 static b8  _wait_events    = 0;
 static i64 _timeout        = 0;
 static i64 _sound_read     = 0;
@@ -2224,7 +2232,16 @@ void p_init(void) {
 
 i32 p_handle_events(void) {
   g_platform.input_size = _input_size;
+  g_platform.cursor_dx  = _cursor_dx;
+  g_platform.cursor_dy  = _cursor_dy;
+  g_platform.wheel_dx   = _wheel_dx;
+  g_platform.wheel_dy   = _wheel_dy;
+
   _input_size = 0;
+  _cursor_dx  = 0;
+  _cursor_dy  = 0;
+  _wheel_dx   = 0;
+  _wheel_dy   = 0;
 
   for (i64 i = 0; i < MAX_NUM_KEYS; ++i)
     g_platform.key_pressed[i] = _key_pressed[i];
@@ -2528,10 +2545,10 @@ __attribute__((export_name("js_frame"))) void js_frame(i32 frame_width, i32 fram
 
 __attribute__((export_name("js_mousemove"))) void js_mousemove(i32 x, i32 y) {
   ++_num_events;
-  g_platform.cursor_dx = x - g_platform.cursor_x;
-  g_platform.cursor_dy = y - g_platform.cursor_y;
-  g_platform.cursor_x  = x;
-  g_platform.cursor_y  = y;
+  _cursor_dx         += x - g_platform.cursor_x;
+  _cursor_dy         += y - g_platform.cursor_y;
+  g_platform.cursor_x = x;
+  g_platform.cursor_y = y;
 }
 
 __attribute__((export_name("js_mousedown"))) void js_mousedown(u32 buttons) {
@@ -2579,6 +2596,12 @@ __attribute__((export_name("js_keyup"))) void js_keyup(u32 key, u32 mod) {
   g_platform.key_down[MOD_META]  = (mod & 8) ? 1 : 0;
 }
 
+__attribute__((export_name("js_wheel"))) void js_wheel(f64 delta_x, f64 delta_y) {
+  ++_num_events;
+  _wheel_dx += delta_x * MOUSE_WHEEL_FACTOR;
+  _wheel_dy += delta_y * MOUSE_WHEEL_FACTOR;
+}
+
 __attribute__((export_name("js_clipboard_size"))) i32 js_clipboard_size(void) {
   return g_platform.clipboard_size;
 }