native_client_sdk/src/examples/api/mouse_lock/mouse_lock.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include <stdarg.h>
   6 #include <stdio.h>
   7 #include <string.h>
   8 #include <cmath>
   9 #include <cstdlib>
  10
  11 #include <algorithm>
  12
  13 #include "mouse_lock.h"
  14
  15 #ifdef WIN32
  16 #undef min
  17 #undef max
  18 #undef PostMessage
  19 #endif
  20
  21 // Indicate the direction of the mouse location relative to the center of the
  22 // view.  These values are used to determine which 2D quadrant the needle lies
  23 // in.
  24 typedef enum {
  25   kLeft = 0,
  26   kRight = 1,
  27   kUp = 2,
  28   kDown = 3
  29 } MouseDirection;
  30
  31 namespace {
  32 const int kCentralSpotRadius = 5;
  33 const uint32_t kReturnKeyCode = 13;
  34 const uint32_t kBackgroundColor = 0xff606060;
  35 const uint32_t kForegroundColor = 0xfff08080;
  36 }  // namespace
  37
  38 MouseLockInstance::~MouseLockInstance() {
  39   free(background_scanline_);
  40   background_scanline_ = NULL;
  41 }
  42
  43 bool MouseLockInstance::Init(uint32_t argc,
  44                              const char* argn[],
  45                              const char* argv[]) {
  46   RequestInputEvents(PP_INPUTEVENT_CLASS_MOUSE | PP_INPUTEVENT_CLASS_KEYBOARD);
  47   return true;
  48 }
  49
  50 bool MouseLockInstance::HandleInputEvent(const pp::InputEvent& event) {
  51   switch (event.GetType()) {
  52     case PP_INPUTEVENT_TYPE_MOUSEDOWN: {
  53       if (mouse_locked_) {
  54         UnlockMouse();
  55       } else {
  56         LockMouse(
  57             callback_factory_.NewCallback(&MouseLockInstance::DidLockMouse));
  58       }
  59       return true;
  60     }
  61
  62     case PP_INPUTEVENT_TYPE_MOUSEMOVE: {
  63       pp::MouseInputEvent mouse_event(event);
  64       mouse_movement_ = mouse_event.GetMovement();
  65       Paint();
  66       return true;
  67     }
  68
  69     case PP_INPUTEVENT_TYPE_KEYDOWN: {
  70       pp::KeyboardInputEvent key_event(event);
  71
  72       // Switch in and out of fullscreen when 'Enter' is hit
  73       if (key_event.GetKeyCode() == kReturnKeyCode) {
  74         // Ignore switch if in transition
  75         if (!is_context_bound_)
  76           return true;
  77
  78         if (fullscreen_.IsFullscreen()) {
  79           if (!fullscreen_.SetFullscreen(false)) {
  80             Log("Could not leave fullscreen mode\n");
  81           } else {
  82             is_context_bound_ = false;
  83           }
  84         } else {
  85           if (!fullscreen_.SetFullscreen(true)) {
  86             Log("Could not enter fullscreen mode\n");
  87           } else {
  88             is_context_bound_ = false;
  89           }
  90         }
  91       }
  92       return true;
  93     }
  94
  95     case PP_INPUTEVENT_TYPE_MOUSEUP:
  96     case PP_INPUTEVENT_TYPE_MOUSEENTER:
  97     case PP_INPUTEVENT_TYPE_MOUSELEAVE:
  98     case PP_INPUTEVENT_TYPE_WHEEL:
  99     case PP_INPUTEVENT_TYPE_RAWKEYDOWN:
 100     case PP_INPUTEVENT_TYPE_KEYUP:
 101     case PP_INPUTEVENT_TYPE_CHAR:
 102     case PP_INPUTEVENT_TYPE_CONTEXTMENU:
 103     case PP_INPUTEVENT_TYPE_IME_COMPOSITION_START:
 104     case PP_INPUTEVENT_TYPE_IME_COMPOSITION_UPDATE:
 105     case PP_INPUTEVENT_TYPE_IME_COMPOSITION_END:
 106     case PP_INPUTEVENT_TYPE_IME_TEXT:
 107     case PP_INPUTEVENT_TYPE_UNDEFINED:
 108     case PP_INPUTEVENT_TYPE_TOUCHSTART:
 109     case PP_INPUTEVENT_TYPE_TOUCHMOVE:
 110     case PP_INPUTEVENT_TYPE_TOUCHEND:
 111     case PP_INPUTEVENT_TYPE_TOUCHCANCEL:
 112     default:
 113       return false;
 114   }
 115 }
 116
 117 void MouseLockInstance::DidChangeView(const pp::View& view) {
 118   // DidChangeView can get called for many reasons, so we only want to
 119   // rebuild the device context if we really need to.
 120
 121   if ((size_ == view.GetRect().size()) &&
 122       (was_fullscreen_ == view.IsFullscreen()) && is_context_bound_) {
 123     Log("DidChangeView SKIP %d,%d FULL=%s CTX Bound=%s",
 124         view.GetRect().width(),
 125         view.GetRect().height(),
 126         view.IsFullscreen() ? "true" : "false",
 127         is_context_bound_ ? "true" : "false");
 128     return;
 129   }
 130
 131   Log("DidChangeView DO %d,%d FULL=%s CTX Bound=%s",
 132       view.GetRect().width(),
 133       view.GetRect().height(),
 134       view.IsFullscreen() ? "true" : "false",
 135       is_context_bound_ ? "true" : "false");
 136
 137   size_ = view.GetRect().size();
 138   device_context_ = pp::Graphics2D(this, size_, false);
 139   waiting_for_flush_completion_ = false;
 140
 141   is_context_bound_ = BindGraphics(device_context_);
 142   if (!is_context_bound_) {
 143     Log("Could not bind to 2D context\n.");
 144     return;
 145   } else {
 146     Log("Bound to 2D context size %d,%d.\n", size_.width(), size_.height());
 147   }
 148
 149   // Create a scanline for fill.
 150   delete[] background_scanline_;
 151   background_scanline_ = new uint32_t[size_.width()];
 152   uint32_t* bg_pixel = background_scanline_;
 153   for (int x = 0; x < size_.width(); ++x) {
 154     *bg_pixel++ = kBackgroundColor;
 155   }
 156
 157   // Remember if we are fullscreen or not
 158   was_fullscreen_ = view.IsFullscreen();
 159
 160   // Paint this context
 161   Paint();
 162 }
 163
 164 void MouseLockInstance::MouseLockLost() {
 165   if (mouse_locked_) {
 166     Log("Mouselock unlocked.\n");
 167     mouse_locked_ = false;
 168     Paint();
 169   }
 170 }
 171
 172 void MouseLockInstance::DidLockMouse(int32_t result) {
 173   mouse_locked_ = result == PP_OK;
 174   if (result != PP_OK) {
 175     Log("Mouselock failed with failed with error number %d.\n", result);
 176   }
 177   mouse_movement_.set_x(0);
 178   mouse_movement_.set_y(0);
 179   Paint();
 180 }
 181
 182 void MouseLockInstance::DidFlush(int32_t result) {
 183   if (result != 0)
 184     Log("Flushed failed with error number %d.\n", result);
 185   waiting_for_flush_completion_ = false;
 186 }
 187
 188 void MouseLockInstance::Paint() {
 189   // If we are already waiting to paint...
 190   if (waiting_for_flush_completion_) {
 191     return;
 192   }
 193
 194   pp::ImageData image = PaintImage(size_);
 195   if (image.is_null()) {
 196     Log("Could not create image data\n");
 197     return;
 198   }
 199
 200   device_context_.ReplaceContents(&image);
 201   waiting_for_flush_completion_ = true;
 202   device_context_.Flush(
 203       callback_factory_.NewCallback(&MouseLockInstance::DidFlush));
 204 }
 205
 206 pp::ImageData MouseLockInstance::PaintImage(const pp::Size& size) {
 207   pp::ImageData image(this, PP_IMAGEDATAFORMAT_BGRA_PREMUL, size, false);
 208   if (image.is_null() || image.data() == NULL) {
 209     Log("Skipping image.\n");
 210     return image;
 211   }
 212
 213   ClearToBackground(&image);
 214
 215   DrawCenterSpot(&image, kForegroundColor);
 216   DrawNeedle(&image, kForegroundColor);
 217   return image;
 218 }
 219
 220 void MouseLockInstance::ClearToBackground(pp::ImageData* image) {
 221   if (image == NULL) {
 222     Log("ClearToBackground with NULL image.");
 223     return;
 224   }
 225   if (background_scanline_ == NULL) {
 226     Log("ClearToBackground with no scanline.");
 227     return;
 228   }
 229   int image_height = image->size().height();
 230   int image_width = image->size().width();
 231
 232   for (int y = 0; y < image_height; ++y) {
 233     uint32_t* scanline = image->GetAddr32(pp::Point(0, y));
 234     memcpy(scanline,
 235            background_scanline_,
 236            image_width * sizeof(*background_scanline_));
 237   }
 238 }
 239
 240 void MouseLockInstance::DrawCenterSpot(pp::ImageData* image,
 241                                        uint32_t spot_color) {
 242   if (image == NULL) {
 243     Log("DrawCenterSpot with NULL image");
 244     return;
 245   }
 246   // Draw the center spot.  The ROI is bounded by the size of the spot, plus
 247   // one pixel.
 248   int center_x = image->size().width() / 2;
 249   int center_y = image->size().height() / 2;
 250   int region_of_interest_radius = kCentralSpotRadius + 1;
 251
 252   pp::Point left_top(std::max(0, center_x - region_of_interest_radius),
 253                      std::max(0, center_y - region_of_interest_radius));
 254   pp::Point right_bottom(
 255       std::min(image->size().width(), center_x + region_of_interest_radius),
 256       std::min(image->size().height(), center_y + region_of_interest_radius));
 257   for (int y = left_top.y(); y < right_bottom.y(); ++y) {
 258     for (int x = left_top.x(); x < right_bottom.x(); ++x) {
 259       if (GetDistance(x, y, center_x, center_y) < kCentralSpotRadius) {
 260         *image->GetAddr32(pp::Point(x, y)) = spot_color;
 261       }
 262     }
 263   }
 264 }
 265
 266 void MouseLockInstance::DrawNeedle(pp::ImageData* image,
 267                                    uint32_t needle_color) {
 268   if (image == NULL) {
 269     Log("DrawNeedle with NULL image");
 270     return;
 271   }
 272   if (GetDistance(mouse_movement_.x(), mouse_movement_.y(), 0, 0) <=
 273       kCentralSpotRadius) {
 274     return;
 275   }
 276
 277   int abs_mouse_x = std::abs(mouse_movement_.x());
 278   int abs_mouse_y = std::abs(mouse_movement_.y());
 279   int center_x = image->size().width() / 2;
 280   int center_y = image->size().height() / 2;
 281   pp::Point vertex(mouse_movement_.x() + center_x,
 282                    mouse_movement_.y() + center_y);
 283   pp::Point anchor_1;
 284   pp::Point anchor_2;
 285   MouseDirection direction = kLeft;
 286
 287   if (abs_mouse_x >= abs_mouse_y) {
 288     anchor_1.set_x(center_x);
 289     anchor_1.set_y(center_y - kCentralSpotRadius);
 290     anchor_2.set_x(center_x);
 291     anchor_2.set_y(center_y + kCentralSpotRadius);
 292     direction = (mouse_movement_.x() < 0) ? kLeft : kRight;
 293     if (direction == kLeft)
 294       anchor_1.swap(anchor_2);
 295   } else {
 296     anchor_1.set_x(center_x + kCentralSpotRadius);
 297     anchor_1.set_y(center_y);
 298     anchor_2.set_x(center_x - kCentralSpotRadius);
 299     anchor_2.set_y(center_y);
 300     direction = (mouse_movement_.y() < 0) ? kUp : kDown;
 301     if (direction == kUp)
 302       anchor_1.swap(anchor_2);
 303   }
 304
 305   pp::Point left_top(std::max(0, center_x - abs_mouse_x),
 306                      std::max(0, center_y - abs_mouse_y));
 307   pp::Point right_bottom(
 308       std::min(image->size().width(), center_x + abs_mouse_x),
 309       std::min(image->size().height(), center_y + abs_mouse_y));
 310   for (int y = left_top.y(); y < right_bottom.y(); ++y) {
 311     for (int x = left_top.x(); x < right_bottom.x(); ++x) {
 312       bool within_bound_1 = ((y - anchor_1.y()) * (vertex.x() - anchor_1.x())) >
 313                             ((vertex.y() - anchor_1.y()) * (x - anchor_1.x()));
 314       bool within_bound_2 = ((y - anchor_2.y()) * (vertex.x() - anchor_2.x())) <
 315                             ((vertex.y() - anchor_2.y()) * (x - anchor_2.x()));
 316       bool within_bound_3 = (direction == kUp && y < center_y) ||
 317                             (direction == kDown && y > center_y) ||
 318                             (direction == kLeft && x < center_x) ||
 319                             (direction == kRight && x > center_x);
 320
 321       if (within_bound_1 && within_bound_2 && within_bound_3) {
 322         *image->GetAddr32(pp::Point(x, y)) = needle_color;
 323       }
 324     }
 325   }
 326 }
 327
 328 void MouseLockInstance::Log(const char* format, ...) {
 329   static PPB_Console* console =
 330       (PPB_Console*)pp::Module::Get()->GetBrowserInterface(
 331           PPB_CONSOLE_INTERFACE);
 332
 333   if (NULL == console)
 334     return;
 335   va_list args;
 336   va_start(args, format);
 337   char buf[512];
 338   vsnprintf(buf, sizeof(buf) - 1, format, args);
 339   buf[sizeof(buf) - 1] = '\0';
 340   va_end(args);
 341
 342   pp::Var value(buf);
 343   console->Log(pp_instance(), PP_LOGLEVEL_ERROR, value.pp_var());
 344 }
 345
 346 // This object is the global object representing this plugin library as long
 347 // as it is loaded.
 348 class MouseLockModule : public pp::Module {
 349  public:
 350   MouseLockModule() : pp::Module() {}
 351   virtual ~MouseLockModule() {}
 352
 353   // Override CreateInstance to create your customized Instance object.
 354   virtual pp::Instance* CreateInstance(PP_Instance instance) {
 355     return new MouseLockInstance(instance);
 356   }
 357 };
 358
 359 namespace pp {
 360
 361 // Factory function for your specialization of the Module object.
 362 Module* CreateModule() { return new MouseLockModule(); }
 363
 364 }  // namespace pp