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用帆布完美的像素碰撞我觉得我靠近就这一个,但我有一些困难,找出我缺少具体是什么。我试图在Canvas中进行“像素完美”碰撞检测。代码可在Github https://github.com/AlexChesser/jsSprite和http://chesser.ca/jsSprite/13-more-pixel-detection.php麻烦与HTML5
假设我已经确定发生微不足道的冲突,下一个阶段是检查重叠区域的像素级别。
到目前为止,我为这个测试代码是:
// Ok, compute the rectangle of overlap:
if (bottom1 > bottom2) { over_bottom = bottom2;
} else { over_bottom = bottom1; }
if (top1 < top2) { over_top = top2;
} else { over_top = top1; }
if (right1 > right2) { over_right = right2;
} else { over_right = right1; }
if (left1 < left2) { over_left = left2;
} else { over_left = left1; }
if (Sprite.debug == 1) {
// again for the purposes of global debuggery I thought it'd be nice to be able to
// draw the area of overlap, but without ruining all other tests
MainContext.fillStyle = "rgb(200,0,0)";
MainContext.fillRect (over_left, over_top, over_right-over_left, over_bottom-over_top);
}
overlap_width = over_right-over_left;
overlap_height = over_bottom-over_top;
if (Sprite.Xpos > obj.Xpos) {
// read the data start at the sprite's right side
var sprite_data_x_start = Sprite.Xpos +Sprite.width -overlap_width;
var obj_data_x_start = obj.Xpos;
} else {
// read the data from the sprites left.
var sprite_data_x_start = Sprite.Xpos;
var obj_data_x_start = obj.Xpos +obj.width -overlap_width;
}
if (Sprite.Ypos > obj.Ypos) {
// read the data start at the sprite's right side
var sprite_data_y_start = Sprite.Ypos +Sprite.height -overlap_height;
var obj_data_y_start = obj.Ypos;
} else {
// read the data from the sprites left.
var sprite_data_y_start = Sprite.Ypos;
var obj_data_y_start = obj.Ypos +obj.height -overlap_height;
}
// 1. get the coordinates of the overlapped area for box object1
// 2. get the coordinates of the overlapped area for this Sprite
// 3. get the data for each into an array using GETIMAGEDATA
// eg:
var sprite_overlap_image = Sprite.ctx.getImageData(sprite_data_x_start,
sprite_data_y_start,
overlap_width,
overlap_height);
var obj_overlap_image = obj.ctx.getImageData( obj_data_x_start,
obj_data_y_start,
overlap_width,
overlap_height);
//soid = sprite_overlap_image.data;
soid = sprite_overlap_image;
GlobalWatchSOID = sprite_overlap_image;
GlobalWatchOOID = obj_overlap_image;
ooid = obj_overlap_image;
//MainContext.putImageData(sprite_overlap_image.data, 100, 100);
//MainContext.putImageData(obj_overlap_image.data, 400, 400);
for (idx in soid.data) {
if (!isNaN(idx)) {
if ((soid.data[idx] == 0 && ooid.data[idx] == 0)) {
return true;
//console.log(idx + ' ' + soid.data[idx] + ' omg hit! ' + ooid.data[idx]);
}
}
}
return false;
通过检查在Chrome调试器的DOM,我知道我肯定能遍历图像中的每个像素,我是什么无法弄清楚为什么我在array1中的索引处的像素与array2中的像素之间的比较似乎没有重叠。
任何人都可以看到我要去哪里错了地方?也许在这里有一个逻辑错误,也许我没有阅读我认为我得到的广场或什么。
我会一直骂个不停和更新,如果我找到,但往往不是,斯塔克的比我聪明很多:)
我真的想看看这个,当我有一个免费的第二,如果它仍然是一个问题 – 2011-04-26 13:42:45
嗨西蒙,这仍然是一个问题,同样我这个周末分心,这个问题看起来有点'不可逾越' 。想着我会看看websocket,node.js和多个迷你电脑,而这个在我脑海中转过身来。 (我也可能试图在Github上找到一个JS游戏引擎,它具有像素冲突并查看他们在做什么)。我敢肯定这一个接近! – 2011-04-26 15:20:16
上周我浏览了一篇关于此的博客文章(http://www.wildbunny.co.uk/blog/2011/04/20/collision-detection-for-dummies/),可能会有帮助。 – robertc 2011-04-27 22:09:22