gears: Allow model rotation with pointer

diff --git a/clients/gears.c b/clients/gears.c
index ca1fda2..c432bc5 100644 (file)
--- a/clients/gears.c
+++ b/clients/gears.c
@@ -36,6 +36,7 @@
 #include <EGL/egl.h>
 #include <EGL/eglext.h>
 
+#include <linux/input.h>
 #include <wayland-client.h>
 
 #include "window.h"
@@ -51,6 +52,14 @@ struct gears {
        EGLContext context;
        GLfloat angle;
 
+       struct {
+               GLfloat rotx;
+               GLfloat roty;
+       } view;
+
+       int button_down;
+       int last_x, last_y;
+
        GLint gear_list[3];
 };
 
@@ -212,10 +221,54 @@ static const struct wl_callback_listener listener = {
        frame_callback
 };
 
+static int
+motion_handler(struct widget *widget, struct input *input,
+               uint32_t time, int32_t x, int32_t y, void *data)
+{
+       struct gears *gears = data;
+       int offset_x, offset_y;
+       float step = 0.5;
+
+       if (gears->button_down) {
+               offset_x = x - gears->last_x;
+               offset_y = y - gears->last_y;
+               gears->last_x = x;
+               gears->last_y = y;
+               gears->view.roty += offset_x * step;
+               gears->view.rotx += offset_y * step;
+               if (gears->view.roty >= 360)
+                       gears->view.roty = gears->view.roty - 360;
+               if (gears->view.roty <= 0)
+                       gears->view.roty = gears->view.roty + 360;
+               if (gears->view.rotx >= 360)
+                       gears->view.rotx = gears->view.rotx - 360;
+               if (gears->view.rotx <= 0)
+                       gears->view.rotx = gears->view.rotx + 360;
+       }
+
+       return POINTER_LEFT_PTR;
+}
+
+static void
+button_handler(struct widget *widget, struct input *input,
+               uint32_t time, int button, int state, void *data)
+{
+       struct gears *gears = data;
+
+       if (button == BTN_LEFT) {
+               if (state) {
+                       gears->button_down = 1;
+                       input_get_position(input,
+                                       &gears->last_x, &gears->last_y);
+               } else {
+                       gears->button_down = 0;
+               }
+       }
+}
+
 static void
 redraw_handler(struct widget *widget, void *data)
 {
-       GLfloat view_rotx = 20.0, view_roty = 30.0, view_rotz = 0.0;
        struct rectangle window_allocation;
        struct rectangle allocation;
        struct wl_callback *callback;
@@ -245,9 +298,8 @@ redraw_handler(struct widget *widget, void *data)
 
        glTranslatef(0.0, 0.0, -50);
 
-       glRotatef(view_rotx, 1.0, 0.0, 0.0);
-       glRotatef(view_roty, 0.0, 1.0, 0.0);
-       glRotatef(view_rotz, 0.0, 0.0, 1.0);
+       glRotatef(gears->view.rotx, 1.0, 0.0, 0.0);
+       glRotatef(gears->view.roty, 0.0, 1.0, 0.0);
 
        glPushMatrix();
        glTranslatef(-3.0, -2.0, 0.0);
@@ -340,6 +392,13 @@ gears_create(struct display *display)
                glEndList();
        }
 
+       gears->button_down = 0;
+       gears->last_x = 0;
+       gears->last_y = 0;
+
+       gears->view.rotx = 20.0;
+       gears->view.roty = 30.0;
+
        glEnable(GL_NORMALIZE);
 
        glMatrixMode(GL_PROJECTION);
@@ -357,6 +416,8 @@ gears_create(struct display *display)
        window_set_user_data(gears->window, gears);
        widget_set_resize_handler(gears->widget, resize_handler);
        widget_set_redraw_handler(gears->widget, redraw_handler);
+       widget_set_button_handler(gears->widget, button_handler);
+       widget_set_motion_handler(gears->widget, motion_handler);
        window_set_keyboard_focus_handler(gears->window,
                                          keyboard_focus_handler);