I have write a simple example that adds a canvas and draw a rectangle with stroke size 20 scale mode none.
The problem is that if I call getBounds() first time I will get a correct result but after I call scale(); the getBounds() function will give me a wrong result.
It will take in cosideration the stroke but stroke has scalemode to none and on the screen nothing happens but in the result I will have a x value smaller. Can sombody tell me how can I fix this?
protected var display :Canvas;
protected function addCanvas():void
{
display = new Canvas();
display.x = display.y = 50;
display.width = 100;
display.height = 100;
display.graphics.clear();
display.graphics.lineStyle( 20, 0x000000, 0.5, true, LineScaleMode.NONE );
display.graphics.beginFill( 0xff0000, 1 );
display.graphics.drawRect(0, 0, 100, 100);
display.graphics.endFill();
area.addChild( display );
traceBounce();
}
protected function scale():void
{
var m :Matrix = display.transform.matrix;
var apply :Matrix = new Matrix();
apply.scale( 2, 1 );
apply.concat( m );
display.transform.matrix = apply;
traceBounce();
}
protected function traceBounce():void
{
trace( display.getBounds( this ) );
}
Setting the width/height and scaling the same display object can give confusing results. Does your Canvas class do anything unusual (e.g. set the scrollRect or add a mask)?
Also you could try getting bounds of the Canvas' parent instead, or setting cacheAsBitmap on the Canvas and seeing if that helps?
Related
I have a Canvas with multiple raster images.
I use onMouseDown on Tool to find select the item which was clicked.
I have a new requirement.
Suppose, two images overlap each other, and the upper image is partially transparent. That makes the lower image visible. But when I try to click on the lower image, obviously I end up choosing the upper image.
Failed Attempt
I tried to use the getPixel(point) function on Raster. I thought if I can figure that the selected pixel is transparent, I can ignore that raster and look for other items. But I am not getting the color value that I am expecting (transparent or not) using this function.
So, my second thought was that I need to change the mousedown event point from the global co-ordinate space to local raster co-ordinate space. It still did not work.
Is there a way to achieve what I want?
Code
tool.onMouseDown = (event) => {
project.activeLayer.children.forEach((item) => {
if (item.contains(event.point)) {
// check if hit was on a transparent raster pixel
const pixel = item.getPixel(event.point)
console.error(pixel.toCSS(true))
// 2nd attempt
const pixel = item.getPixel(item.globalToLocal(event.point))
console.error(pixel.toCSS(true))
}
}
}
There is a simpler way to do what you want to achieve.
You can rely on project.hitTestAll() method to do a hit test on all items.
Then, if the hit item is a raster, hit pixel color information will be contained in hitResult.color. hitResult.color.alpha is all you need to check if a raster was hit on a non-transparent pixel.
Here is a sketch demonstration of the solution.
const dataUrl = 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAIMAAACDCAYAAACunahmAAAZIklEQVR4Xu1dCZgdVZU+51YvMd3KImDQICF0Xt3qTgIaFQdBGUTFbVxHUFxGZRRlZNzHEXXQURQYl3HD3RFmxnVERUQUNQ6jiEPL2l23XjoxYICgDqhJoMl7VcfvZ6rzNU1317n16r1e0uf7+PLxvXvPPffW31X3nuW/TEuytAL5CvDSSiytwMQKLIFhCQt7VmAJDEtgWALDEgbuvwJLb4ZpUBFF0aEiwkEQLG82m48wxvwhy7LbiehhIrI1y7Jb0W1sbOx3iwlUeyUY1q1bt9/u3bv3JaINRGSJ6IHGmHUicggR9RPRqoKHPJ7/fpOIbGPmPxLRdUR0c5ZlY8x8XZIkOxYaUPYKMAwNDa1I0/SZRHQYER1FRI/JH3pbnpeI/IGZ8da4jpk3Zll2bZqmV4+Njd3TlgErUrpowRCGYUhErzDGHC0iePg9Fa1ZWTW3EdHPiKjOzBc3Go3RsbGxP5VV1o5+iw4MURS9REReQETPaMeCVagTQPg5M1/GzD8dHR29pkLdpVQtGjBEUfRYEXkrET2n1ErMcScRuYKIvhEEwVWjo6NXzYU5Cx4M1lps9j60UEEww0P/KRH9FxFd7Jzb2ilgLGQwBNbajxDRa4go6NSCdXicVET+k4guS5LkP9o99oIEg7UWJ4Nz82Nhu9dovujfJCIf6u/vv2B4ePiudhi14MAQhuEnmPm17ViMBaJzm4i8IUmSb1Rt74IBw+Dg4FCapucz87FVL8IC1fcLZn5nHMeXV2X/ggCDtRbHxG8Tkalq4pP07Cai34nIFmPMdhGBP2BERO4yxtycpundxphxZpYsyw4yxizLPZS9RLRGRCIiOpCI4NfoaoN9s6oUkXcmSfI+IpJWx573YLDWfoaI/rbViU7qfxMRXU1EG0XkN81m88rNmzfDW9jSYkZRdDARHZpl2SAzP4KIHk1EjySi7gptn0nVJmY+OY7jX7Uy1rwFg7X2wUT0TSJ6fCsTzPsiyHR+lmXfq9fr/1uBPpWK3A2+XkSOZ+anEdFaImrnmr/ZOfdBlXHTNGqnYWVtoqGhocE0TTfmr9/SeohoOzOfu2PHjk9t27bt7lYUVdF3YGBgZRAET0aAjJn/iohWVqF3io7POudeVUbvvAODtfZFRPTFFmMJO4nooyLygXkcPQxqtdpaYww8pidVfEweIaIXOudu8AHFvAKDtfafiOgsnwlM0/YrzPzGOI6xEVwwAnd6lmWnMvNTKnpjwGH1wiRJvq5dhHkDBmstPG0v1Bo+Tbs/MvMpcRxf0oKO+dA1CMPwZGZ+MRGdWIFBH3bOvVGjZ16AoQIgfIeZT1tob4OiBxRF0Uki8qb8ZFLUfLbfz3LOvbtIwVyDgcMw/G6+0y6ydabfVRMtq3w+9AvD8DRmfk+LG+ovO+ewH5tR5hQM1tr/IaLHlVzwncz83DiOf1iy/4LqduSRR+47Pj5+YYt5Gl9esWLFSzdu3NicbvJzAoYNGzYs37lz58+Y+ciST+SnWZadUq/XbynZf8F2s9bi2PjpFibwK+cccj/vJ3MChiiKrhCRY0pO6DPOuVeX7Lsoug0ODh6VZdm/lT2OMvPX4zhGNth9pONgCMPwcmZ+Ysmn8ibnHBJZloQI+Rzw0MJ5VUa+6Jx7xeSOHQWDtfbLRHRyCcuFmZ8Xx/FFJfou6i7WWpw2/qXMJEXkqUmSfH+ib8fAYK39DhEhKcVXkDh6onPuSt+OZdsPDAz0BkHQ09PT09VoNFaKyO40TXcFQbB/mqZ3ENGfjDE99Xr992XHqLJf7rXFZ8MrKCYi32Pmt014KjsChiiK3isiZ5ZYgG1BEDx6ZGRke4m+hV1Wr169T09Pz1EistIYg4DSgSKyLzM/iogQokY6HYpqIFkeQse/cHdj4X9DRPB03iMi1xKRM8bEcRz/onDwihvk8ZwbPQNhv2bms+M4/hzMaTsYwjB8ATN/tcTctxHRsVUmhFpra3kNBYJFSKRdx8yorKparhcRVFhd3dXV9a2RkZGbqx5gOn3WWpwS8No/QDmeE5H3TuRXthUMec1imeze33d3d9duuOGGO5WTmrZZGIYPJaKjjTHH4/uoKJtrZbiZ+qZEdJWIXNrV1XVBu4ERhuFhzIy31IMUk/lSlmVnThzR2waG9evX9+3evRuvraK6xak238TMT4jjGEko3lKr1Q4wxjw99+s/t8Xop/f4BR3wifklorLOOSTttEXy8oGkaO5pmg5u2rQpnjCibWCw1qKU7GjP2d6RZVlYZmMWhuF6Ino+M78ehbSe485Fc4D94iAIzmvH28Ja+xdEhPqLmTaVr3LOfXbyxNsChpIbxt9j4+b7Rsh3/h9awBnTd4vIx4wxn/SdexGCa7WaNcacQ0TYIyF3EzLMzO+N4/hbU/tXDoYoip4mIt5hZGPM2tHRUSRlqMVai9As/nuYutP8bdhk5jNF5PPOuf+r0szDDz/8oJ6entXgmEiS5Ncz6a4UDMcdd1zX9u3bcQxE/qJamPlJPinfeX4ksqHK+C3Uds1Rw504hidJ8tFOj18pGKy1ONYgU0ctzPyuOI7/WdshiqJXisiHF8i+QDut6dohg/sdzrnLWlHi07cyMIRh+JfM/GOvwZnPj+NYXR2VfxZKZ//62DZf2ubf93d2wp5KwDA0NNSTpim+RTjXayVxzoFCRyXWWrhbX6ZqXK5RJiK3GGPgUbxRRHYx87Ysy+AOB+PKDmZGbQSKbh5ORA8gIjisVhPR4RXlLc5k+SYiep5vgqvvMlQCBmstvt9/4zH4Xd3d3Su1TiVr7XlE9GYP/YVN4T42xuCh/xIcTI1GY8vY2Bi8nmXE1Gq1mjFmSEROZGbUetTKKJqlD3wUp009DlY5RstgiKLokSIy7GnUM51z39X0sdZ+jIj+TtO2oA1IuC4VkR8EQXDF6OjoWAU6Z1RRq9WOCYIA4eVn5CV4lQzHnp9Wn0FbBoO1FtlGPp+HjzvnXqcx0lqLJJZPadrO1IaZv5ZlGd5cPyuqocjd1/h03ZIkCTx4lUgURU8XEeQfzpqDqB0M0cZGo/GiLVu2AOCVSUtgCMMQr8RLPaz5k3NufyKCv35WyeMa+OstW8x6AeL8mu/smjVroiAIkHCKv+QJIrCNzPyFRqPx87Gxsc1F9mp+D8PwccaYU0QEBCMtCTMjOjrYkpIpnUuDIfcpYNOoLhHLYw7/rZmAtRbuWmzUfOUqeCO1Rag5F9TPCyK4+KS9rqoIav5pxafv5b6Tm9L+ShF5StEbTztGaTCEYfhy/OVoByKiLznnVJvM3Jdwb4zdR0Tk3CRJ/kHbJz8FIUFFE8vYGQTBUJVxBGvtcfnGGIG1UlLlG6I0GKIoGvXYGN3unFuhmS0yp3ft2rWFiB6iaZ+3aYrI85MkAYeDWkrsSW7Lsuz4er3u1IMoGkZRdKqIwPGmWqNpVH7TOfc8xVCzNikFhjzNSk04JSKvTJJE9RYpEeTCuf9Rmr3B1JWw1sK7hyCOj9y9bNmyh1577bV/8OlU1DYMQ1AWfzXPuyhqfr/fZ8p49lFUFgw/ISK84jRyo3NunaYh2lhrcdZXB57AfZAkCezxFmutzzwm6/++cw7JMpWLtRYnrVJxCRF5tu/bcfIEvMFgrcWDvd5jFZDMqvKvR1H0WhH5hIfuM5xz8EOUkjAMz4S7t1Tn/3cAtVLMMuOw+V4ChcjwePpK6Jyr+3ZC+zJgUGc5M/Mv4zgGcbdKrLV49e6jakz0C+ccEjhKS16yVjq1rtFoPGTz5s2/LW3ALB0Rdu7u7kZGONzdaoFnNUkS0Ah5ixcYNmzY0L1r1y48sOXKkeBPR6FHodRqtSOMMcjd08r6MvuEqcrDMHwxM6OGsYxc4JxrW7wk30yDdsjLn1D2c+EFhjAM/56ZwcqqkVtWrFixaqYiz6kKrLVfIqKXahT7vnGKdIZh+Apmxm7ex5N6r9osy46q1+vIa2yL5DmdeEMMeAywa3x8/ICtW7dO3Iuh6uoFhiiKkOULun6NvMc5ByYWjaBUDJd1IBJYKMaYx4+OjoJ4uzJB+lx3d/fjReQMz0rnHzvnypYLquzP6zuQNDSRulbYj5lfFscxvLBqUYMB1HagylPyNN/TbDYHtFFA3A3BzKqzeyvfRO2qhGF4jUeFeMM5h4eEqGLbJPeU+lSVjTjnwC6nFjUYrLUgnny7UrNXpbS1Fqwi71LqfrlzDrkNbZNarbbaGKOORzDzqXEcf75tBuWKrbX/SERna8fxtcsHDBdrX5/GmBNGR0d/pDU6DMOLmPnZivbNLMtWdYKXwVqLjCoVFxKKZJxzj1XY33ITT8/vJc459SUsKjDkpwgEpTTOoK3OOdwFpRZrLTZgYFQtkhmJJoo6+v6exy1w7NScnHY551DB1NZPBeYQRdGTkJOhnM+O7u7uQ7VJRCowRFF0goio6HJ8ky/y6p8Z07enTPrTzrnTlAvRcrMoij4vIvfhMJhJaZZlR9brddRXtl2stSgpUB03ReS1SZKcrzFKCwZkJKuiiMz8ZB+epcHBwWOzLFOFtVEx5ZzDDS0dEWstyvO0473FOVeKJ8F3Mp6xIXW0WAUGnw1es9k8yOfyT59dcjuOlLM9CGQ+MbOWN+ps51wZ2gFfLNzb3lqL0LumPuU25xzu6yxMKFKBIYqi7ymjadc7547wmZ1H7oIEQbCqynwCjZ3WWmRHF+Y7MPPpcRx/UqOzijbWWlw+ogpbZ1l2bL1eB7PerKICg7UW+4UTipQR0eXOuScp2u1p4vHW2d1oNA5pVyxgOpu11cx53/c757RHb58lmrZtFEXPERGVqx9XO2pogwvBkKe3jeKijaIZYF+RJInX3RBRFJ0sIuB6KhKwwh9SdR3ibIP6MNeKyEeSJHlD0SSq+n3t2rUPaTabWkabTzjnCjPMC8HgSbiBPMGP+0w4DEOU0avIrpl5XRzH4Hxou+T0emo6npygtKMEZNZanF5ARVAkqs93IRjWrl17SLPZ1NLQvNqXhMInagjuyCRJwPvQVsmjhahiUgWumHnz8uXLo+Hh4UZbDZuiPIqiC0UEhONFMuycA0/VrFIIhqGhoSPTNFVdzetbTQ3LoihaKyLaexG8wVa0AFN/zyu8QXIx5NF3TvgpPVIEt4+Pjx9WFMUsBIO1FlXVe7gCZ1ugMilo+V8h+Ag0ETk1Xb7Hg9zTNL8YDXEPzZFtT788KKeOZZSxbbo+PilyeWY39n4zSiEYUPjBzIXHEozAzBu09QqTLAKzPHiccBYukiudc77UQEU6cQ0SCofhMFJVek1WyMz/GscxqIM6Lh6bb1VMpxAMPt4uY8yaMjWMHt8+6urqeviNN96IUHolYq1FLQfyLnyJyDA+YhITPJGV2OOjxIMlB6UEtdlYW+79Yy4aPAzD1zCzypmieRXN8LrzCc1e09PTc+z111+/q8j2mX6PomhNlmXgp0SktHBjNcs43qensjZP1y+KopeIiDaB5XHOOVSOlf9M5EWjmorpNMuyQ8uEl8MwfBYz349waha7bxKRtx588MHfLEqrw4aQmXHf5DHGmNUiguolnxSymcxoa/6jBjQeta6VfSaQ8KlNJimVpLpq1aply5YtQwwARbk+gj7ImwDxKC7oWm6MMSKC/Uc/M0cignRzTRhaPa6IXJEkSRX3barHnK5hnrupSarJsixbU6/XUanW0ptB6yFEcmhUtvQsiqLTRcTLYdXSSpbvfEOz2Xz02NgY2FzmVPKyvPtwOc5kkIjYIpqBwj1DFEVIEsW5u1DK0PdNKF23bt1+jUYDjO3zWS7q6+s7qdPOpZkWJAzDM3CaUSzYrc45VLTPGrksBIPP97zVELO1FheLdMy/r1jEyU3mfI8w1d4ois4Vkbco5gEwgDph1vu+C8GQ087OugudMKZVMECPT3BIsQhVNEHeADyfqghhFQNqdXiQnt3snMPRuTUweGYKn+KcQ41gS2KtRTDKxx3c0nizdP5Ks9k8wydZp12GTKfXWgsScA1j3kXOOWRtzSqFb4acf3gP83iBvkrS2PMqIpTaaRJwi+bo/TsCT0T04rm4RERr7MqVKx/Q39+PhF1cklIkqtzRQjB4kmeo4uZFluP3oaGh/mazeU4nCcLza3q+5pxD7WXbM5016zBTm8HBwSdmWXa5UsfbnXPvL2pbCIb8O46z/PFFyojoh845X/KLWdVaa3E/9gdK8jspTKarmfknWZZ9P0kSL4ZbjfJ2tQnD8B15fahmCJCZFNIzasGgZTjxLunSzAR3Q0VR9CwwxIoI/i0ruFsK2UGXgbvSGHNdicBa2bEr7WetRdhfUz7X7Ovr22d4ePiuIgNUYAjD8D3MrOUvPqwqVrTpjMclI8aYI+D6ZubnIyWCiMCHiLk8WES2MTP8Fbh0A8W5m0D9i/uiGo3Gpqq5E4sWuB2/5zkX2pvzrnHOPVJjhwoMHqFSjFkYENEYpm0zMDBwYLPZ3NFsNnn58uX71+t1cD/P6++9dm4ztbPWnpVHWjWq1PUcKjBYa59ARBs1I8NI5xwINpekTSuQ0xdoQ+dHa+8EVYEhT/5AHmQhHR925EmSlOY1bNP6LRq1HlFkzNmLMEUFBmi11iI+oYnU3bF79+7Vi+HbPB8R5LFxJBF5R5IkoFJQiRoMYRh+FvX+Gq0i8sSFdEzTzGk+tLHW4tiuYs7L7VV/ItDeBwzHM7OWc6Gj1UXz4UF1wgZrLdL9VFzdyFuN4/hYH7vUYPAMMd+Zs8f72LLUdpYVsNbi8hVcwqKSMmULajDk+wacKHCyKBTf0vxChXtxAx/Oq3yZ7urr69vXN+/CFww+KXCXOedO3IufYSVTz4lLwfh6oFZhGaY3rz0DGvsidNmyZftVTbitXZDF0C6PTKLeU1NPOTHl3zrnCl0A062P15sh/1Ro+ZfQHBeAq2hwFsPDq3IOOVEIAmehp94XOec0Ve33U1sGDCg6wZ1PKunr6+vTBElUyvaSRjn3AjLSQRrmIz9wznldMjtZuTcYcC8CM4PNRCuV5ThoB1yo7fIAFFjyEbb3FhFZXVQ1NZtSbzBAWRiGH2Zmn/rCAzpJsuG9ivOgQx4MxLXOpW6jYea3xXF8TitTKQWGnMvY5yaWjpFmtrIYc9G3Vqs9xhgDEvPSSUEi8skkSU5v1f5SYMCgURR9TUT+WmuAiJyTJMnbtO0Xe7uc3BNV389sca4qIg7NGKXB4OmRnLBlrw5vgwUnTdOngKiTiEpdEDLloYKi4Jiq8jdKgyHfO1zCzE/ToG5Sm3c755CcsddI/ilAkA/H7KCiid8+Pj6+qoiNxWeslsCQ11TAO+Y7wUUfyMrL/p/KzOBc0vBi+zy3bzQajdOrpkFsCQz520Fb73efyYrIj7q6ul4wMjIy3+sr1Q8Jn4FGo3EybvYlonYl+HzQOYegVeXSMhhgkUdlz1RA4ETyJu2dl5XPvgKFKDJCYi4zI/EHN9KYCtROpyJh5tf58HL72lEJGAYGBh7U1dWFm2TKXL0Hm7/bbDZfX9UF5L6L4NM+v1XuqbieKd8vlaH/8RkSGUsX9vf3v9I3Cuk1iE9yS5HiMAwfxcy4aa2sgEPxvGaz+YX5AgrQBed3cj3YGHO0iOBOT8QKNMx0ZddhTz/ccy0ipxbR77Q8UK6gkjfDhDEepOBF9iNAcykR3Ypil0ajsX3Lli240KylFPj169f33XHHHVlvb+8De3t7H5amacrMoPR5oIjsk9P8IB5whIgcqGSgK5pLmd/BSPMBX7bdMgNN7lMpGKDYh/7Xw3hUQmF/gQtFwZhyExF1IUYiIuCUBm/j75h5hYgEItIAjxOKZ5gZ1ECg9AHjGVy9KEsHrU9H/ro95oimuITlK0EQnD0yMoI5d1QqB0MOCNwTidtPejo6m4U72A25S/lTczmFtoABExocHBzIsgw0w9pij7lch7kYG2+4y7Ise187L0n1mVjbwAAjBgYGDu/q6kJ5e0t3VvtMaAG0xaXyFwZB8O8jIyPaKwI6Mq22gmHSxlLLPdSRSc/BIGO4cS4Igs+Njo6qSNnnwEZ93USrxuVlYbippXLu51Zta1N/UBHhqA1iMG2daptM0antyJthsinWWjCILNZQNuI0lxDRt51zKrpE3WPqTKuOgwHTstbWiAh80cinXMiC9D9Q6VxpjLnG55bf+TjpOQHDpL3EY0UEyR24hc03C7jT63mniPyKmbeIyDXGmCvuueee3yymAuM5BcPkpxlF0UlZlj3CGHOYiBxHRAd1+GmD/QURVHBQD+M+S2aGowt1C1uNMbfNhSOok2swb8AwedIDAwO9vb29KATZP03To3J3cS8zgxuSmdlkWVZj5gn6ngPARQAnFzMjt2KriOzHzPhr3s7MfVmW3QrvJYjG4cEUEei40xizWUQ4TdPbxsbGfLK+O/mcOjLWvATDlJkHYRgu7+rq6k7TFJ8SxsPDZyX/y8X/H8TMqFDuyd3R+EveP3/Yvw2CYHmaprc3m81Gf3+/Warymh5bCwEMHfmrWBrEg59habEW/wosvRkW/zNWz3AJDOqlWvwNl8Cw+J+xeoZLYFAv1eJvuASGxf+M1TNcAoN6qRZ/wyUwLP5nrJ7hEhjUS7X4G/4ZfCcCGmFmZeQAAAAASUVORK5CYII=';
const lowOpacity = 0.3;
// create 2 rasters
new Raster({
source: dataUrl,
opacity: lowOpacity,
onLoad: function() {
this.position = view.center - 100;
}
});
new Raster({
source: dataUrl,
opacity: lowOpacity,
onLoad: function() {
this.position = view.center + 100;
}
});
// on mouse down
function onMouseDown(event) {
// unselect previously selected items
paper.project.selectedItems.forEach(item => {
item.selected = false;
item.opacity = lowOpacity;
});
// do a hit test on all project items
const hitResults = project.hitTestAll(event.point);
// for each hit result
for (let i = 0; i < hitResults.length; i++) {
const hitResult = hitResults[i];
// if item was hit on a non transparent pixel
if (hitResult && hitResult.color && hitResult.color.alpha > 0) {
// select item
hitResult.item.selected = true;
hitResult.item.opacity = 1;
// break loop
break;
}
}
}
Instead of rotating the camera with camera.rotation or with the lookAt() function
I'd like to pass a look vector directly to the camera... Is it possible to set a camera look vector directly and is it possible to read the look vector from the camera?
The camera does not have a "look vector", so you cannot set it.
You can, however, construct a point to look at by adding your look vector to the camera's position, and then calling
camera.lookAt( point );
Here is how to determine the direction in which the camera is looking, assuming the camera either has no parent (other than the scene).
The camera is looking down its internal negative z-axis, so create a vector pointing down the negative z-axis:
var vector = new THREE.Vector3( 0, 0, - 1 );
Now, apply the same rotation to the vector that is applied to the camera:
vector.applyQuaternion( camera.quaternion );
The resulting vector will be pointing in the direction that the camera is looking.
Alternatively, you can use the following method, which works even if the camera is a child of another object:
camera.getWorldDirection( dirVector );
three.js r.73
These other answers are very insightful, but not completely correct. The code returns a vector that points in the same direction that the camera is pointing at. That's a great start!
But unless the camera is at the origin (0, 0, 0) (or lies exactly on the line segment that connects the origin to the rotated vector point without passing beyond that point so that the point is behind the camera) the camera won't be looking at that point. Clearly -- just common sense -- the position of the camera also influences what points are being looked at. Just think about it!!
The camera method lookAt() looks at a point in 3D space regardless of where the camera is. So to get a point that the camera is looking at you need to adjust for the camera position by calling:
vec.add( camera.position );
It is also worth mentioning that the camera is looking not at a single point but is looking down a line of an infinite number of points, each at a different distance from the camera. The code from the other answers returns a vector that is exactly one unit in length because the application of a quaternion to the normalized z-axis vector (0, 0, -1) returns another normalized vector (in a different direction). To calculate the look at point at an arbitrary distance x from the camera use:
THREE.Vector3( 0, 0, -x ).applyQuaternion( camera.quaternion ).add( camera.position );
This takes a point along the z-axis at a distance x from the origin, rotates it to the direction of the camera and then creates a "world point" by adding the camera's position. We want a "world point" (and not just a "relative to the camera point") since camera.lookAt() also takes a "world point" as a parameter.
The above answer wrapped as a util, this is what I do with my Three Utils:
THREE.Utils = {
cameraLookDir: function(camera) {
var vector = new THREE.Vector3(0, 0, -1);
vector.applyEuler(camera.rotation, camera.eulerOrder);
return vector;
}
};
Call it with THREE.Utils.cameraLookDir(camera);
What I did was to use method lookAt(Vector) just before render the scene like in below code , just try it using it on a new html file :)
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
<style >
*{
margin: 0 ;
}
#WebGlElement {
height: 500px;
width: 500px;
background-color: red
}
</style>
</head>
<body>
<script src="js/three.min.js"></script>
<div id="WebGlElement"></div>
<script>
var contianer = document.getElementById("WebGlElement");
var origin = new THREE.Vector3(0,0,0);
// CREATE THREE BASIC ELEMENTS
var scene = new THREE.Scene();
var camera = new THREE.PerspectiveCamera( 40, 300/300, 1, 1000 );
var renderer = new THREE.WebGLRenderer();
// SET RENDERER AND ATTACH IT TO BODY
renderer.setSize( 500, 500 );
//document.body.appendChild( renderer.domElement );
contianer.appendChild( renderer.domElement);
// CREATE A GEOMETRY AND ADD IT TO SCENE
/*var geometry = new THREE.BoxGeometry( 1, 1, 5 );
var material = new THREE.MeshBasicMaterial( { color: 0x1abc9c } );
material.wireframe = true ;
material.wireframeLinewidth = 0.1 ;
var cube = new THREE.Mesh( geometry, material );
scene.add( cube );*/
var geometry = new THREE.Geometry();
geometry.elementsNeedUpdate=true;
geometry.vertices.push(
new THREE.Vector3( -0, 1, 0 ),
new THREE.Vector3( -1, -1, 0 ),
new THREE.Vector3( 1, -1, 0 )
);
geometry.faces.push(
new THREE.Face3( 0, 1, 2 ),
new THREE.Face3( 2, 1, 0 )
);
var material = new THREE.MeshBasicMaterial( { color: 0x1abc9c } );
//material.wireframe = true ;
//material.wireframeLinewidth = 0.1 ;
var cube = new THREE.Mesh( geometry, material );
scene.add( cube );
var axisHelper = new THREE.AxisHelper( 1 );
scene.add( axisHelper );
// POSITION OF CAMER ON Z
camera.position.z = 5;
camera.position.y = 5;
camera.up = new THREE.Vector3(0,0,1);
var dir = 1;
var number = 0.115
// CREATE FUNCTION FOR RENDER
var render = function () {
requestAnimationFrame( render );
//circle.rotation.x += 0.01;
if ( camera.position.x> 5) {
dir = -1;
}
if ( camera.position.x< -5) {
dir = 1;
}
camera.lookAt(cube.position);
//camera.rotation.y += 0.015 * dir;
camera.position.x += number * dir;
renderer.render(scene, camera);
};
// EXECUTE FIRST RENDER
render();
</script>
</body>
</html>
In a drag+drop situation using Flex, I am trying to get the object center aligned to the point of drop- somehow, irrespective of the adjustments to height and width, it is always positioning drop point to left top.
here is the code..
imageX = SkinnableContainer(event.currentTarget).mouseX;
imageY = SkinnableContainer(event.currentTarget).mouseY;
// Error checks if imageX/imageY dont satisfy certain conditions- move to a default position
// img.width and img.height are both defined and traced to be 10- idea to center image to drop point
Image(event.dragInitiator).x = imageX-(img.width)/2;
Image(event.dragInitiator).y = imageY-(img.height)/2
The last 2 lines don't seem to have any effect. Any ideas why-must be something straightforward, that I am missing...
You can use the following snippet:
private function on_drag_start(event:MouseEvent):void
{
var drag_source:DragSource = new DragSource();
var drag_initiator:UIComponent = event.currentTarget as UIComponent;
var thumbnail:Image = new Image();
// Thumbnail initialization code goes here
var offset:Point = this.localToGlobal(new Point(0, 0));
offset.x -= event.stageX;
offset.y -= event.stageY;
DragManager.doDrag(drag_initiator, drag_source, event, thumbnail, offset.x + thumbnail.width / 2, offset.y + thumbnail.height / 2, 1.0);
}
Here is one important detail. The snippet uses stage coordinate system.
If you use event.localX and event.localY, this approach will fail in some cases. For example, you click-and-drag a movie clip. If you use localX and localY instead of stage coordinates, localX and localY will define coordinates in currently clicked part of the movie clip, not in the whole movie clip.
Use the xOffset and yOffset properties in the doDrag method of DragManager.
Look here for an example.
This is my attempt to write my own layout class for a panel of buttons (which may have between 2 and 20 buttons). Basically they should all be of a uniform size, with a constant spacing (5px) and resize appropriately.
However it doesn't always work.
Sometimes it works absolutely fine, but others it gives space for an extra column, or becomes unable to add additional columns on resizing (removing columns is fine), or something wont work. And it takes ages and seems horribly expensive in terms of computations. Reducing width seems significantly more painful in this respect for some reason.
Anyway, here it is:
package layouts
{
import mx.core.ILayoutElement;
import spark.components.supportClasses.GroupBase;
import spark.layouts.supportClasses.LayoutBase;
public class QButtonsLayout extends LayoutBase
{
public function QButtonsLayout()
{
super();
}
override public function measure():void
{
super.measure();
target.measuredHeight = 130;
}
override public function updateDisplayList(w:Number, h:Number):void
{
super.updateDisplayList(w,h);
var tCount:int = target.numElements; // Number of elements
var tW:Number = target.width; // Width of target (button area) - somewhere between 550 and 1000px
var maxW:Number = 1; // Largest natural width of any given element
var maxH:Number = 1; // Largest natural height of any given element
var eSetW:Number = 1; // Set (to be) width of each element upon the target
var eSetH:Number = 1; // Set (to be) height of each element upon the target
var tCols:Number = 1; // Number of columns upon the target
var tRows:Number = 1; // Number of rows upon the target
for (var i:int = 0; i<tCount; i++) // Find maxW
{
var layoutElement:ILayoutElement = useVirtualLayout ? target.getVirtualElementAt(i):target.getElementAt(i);
var thisW:Number = layoutElement.getPreferredBoundsWidth();
var thisH:Number = layoutElement.getPreferredBoundsHeight();
if(thisW > maxW)
{
maxW = thisW;
};
if(thisH > maxH)
{
maxH = thisH;
};
}
tCols = Math.floor((tW-5)/(maxW+5)); //Find maximum number of columns one can fit onto the target
if(tCols>tCount) //Fix to deal with cases with low tCounts
{
tCols = tCount;
};
tRows = Math.ceil(tCount/tCols); //Find corresponding number of rows
eSetW = ((tW-5)/tCols)-5; //Set widths of elements based upon number of columns, 5s to add some space between elements
eSetH = maxH; //Takes height as the largest height
for (var j:int = 0; j<tCount; j++)
{
var layoutElement2:ILayoutElement = useVirtualLayout ? target.getVirtualElementAt(j):target.getElementAt(j);
var eRow:int = Math.floor(j/tRows); //Row of given element, taking the 1st to be zero
var eCol:int = j - eRow*tRows; // Column of given element, again taking the 1st column as zero
var _x:Number = 5 + eRow*(eSetW+5);
var _y:Number = 5 + eCol*(eSetH+5);
layoutElement2.setLayoutBoundsPosition(_x,_y);
layoutElement2.setLayoutBoundsSize(eSetW,eSetH);
}
}
}
}
Any thoughts would be much appreciated.
Criticism more than welcome.
Turns out that it's not. The layout class itself is fine, as far as calculating element positions and size is concerned.
It is actually a problem in the way in which the buttons used calculated their prefered widths. Whilst I'm not versed in the actual manner in which this happens, it was solved by removing %width values for any height and width values for graphic elements within the button skins. (Eg changing width="100%" to left="0" right="0").
I hope this might help someone, somewhere, sometime.
I have an item renderer for a grid that has a fairly basic updateDisplayList function:
override protected function updateDisplayList( w : Number, h : Number ) : void
{
super.updateDisplayList( w, h );
var labelWidth : Number = Math.min( _labelDisplay.measuredWidth, w );
var labelHeight : Number = Math.min( _labelDisplay.measuredHeight, h );
_labelDisplay.setActualSize( labelWidth, labelHeight );
var labelX : Number = ( w - _labelDisplay.width ) / 2;
var labelY : Number = ( h - _labelDisplay.height ) / 2;
_labelDisplay.move( labelX, labelY );
//this is just for debugging
graphics.clear();
graphics.beginFill( 0xFF0000, 0.5 );
graphics.drawRect( labelX, labelY, labelWidth, labelHeight );
graphics.endFill();
}
where _labelDisplay is a spark label. When I scroll the grid (this is a cuatom grid, not mx:Grid or AndvancedDataGrid) when new rows appear at the bottom of the grid updateDisplayList is called and the code to re-draw the background and move / resize the label executes.
The problem is that these chanegs are not reflected in the view. The text is mis-aligned as a label that used to display a large string now displays a short string so the measuredWidth has changed.
The next time I scroll the renders update to look like they should - but updateDisplayList is NOT called here (on the renderes). All that happens is that the renderers are re-positioned in the grid.
Both the background and the label are displayed incorrectly initially so it's not just the label mis-behaving.
Anyone got any idea why this is happening?
Thanks
Just a guess, but does this make any difference?
override protected function updateDisplayList( w : Number, h : Number ) : void
{
var labelWidth : Number = Math.min( _labelDisplay.measuredWidth, w );
var labelHeight : Number = Math.min( _labelDisplay.measuredHeight, h );
_labelDisplay.setActualSize( labelWidth, labelHeight );
var labelX : Number = ( w - _labelDisplay.width ) / 2;
var labelY : Number = ( h - _labelDisplay.height ) / 2;
_labelDisplay.move( labelX, labelY );
super.updateDisplayList( w, h ); // Call updateDisplayList after moving / resizing _labelDisplay
}