Add SpriteFrame support for AutoPolygon

[zawasp]

Right now AutoPolygon only supports generating PolygonInfo's from individual sprite files. We need to create them from a given SpriteFrame (loaded from SpriteFrameCache).

Currently, there's no direct way to do this.

[fusijie]

@zawasp You can specify a rect for sprite sheet, please refer to polygon sprite test case 2.

    auto filename = s_pathGrossini;
    Rect head = Rect(30,25,25,25);
    auto pinfo = AutoPolygon::generatePolygon(filename, head);
    spp = Sprite::create(pinfo);
    addChild(spp);

[zawasp]

@fusijie I know, but there's no direct way of doing it, eg:

auto pinfo = AutoPolygon::generatePolygonFromSpriteFrameName(spriteName);
spp = Sprite::create(pinfo);

More (and worse) than this, the AutoPolygon constructor will reload the same SpriteSheet texture file each time it's called, for each SpriteFrame. This takes a lot of time for large spritesheets. It should just lookup the texture name in the texture cache.

[fusijie]

@zawasp Yes, you are right. Polygon Sprite is not a mature product, and I think we need a detailed discuss about it and relative tool.

[CodeAndWeb]

I've extended SpriteFrameCache to load sprite frames with polygon information from a plist file. The format now contains 3 new optional values which can be used to pass the vertices and triangles:

• triangles: 3 indices per triangle, pointing to vertices and verticesUV coordinates
• vertices: vertices in sprite coordinates, each vertex consists of a pair of x and y coordinates
• verticesUV: vertices in the sprite sheet, each vertex consists of a pair of x and y coordinates

The SpriteFrameCache creates standard quad sprites If these additional values are not present.

The API from a user's perspective is untouched. You simple load the plist file using

SpriteFrameCache::getInstance()->addSpriteFramesWithFile("spritesheet.plist");

The sprites are created as usual:

auto sprite = Sprite::createWithSpriteFrameName("grossini-dance-05.png");

I've just opened a pull request here: https://github.com/cocos2d/cocos2d-x/pull/14049

Plist files with polygon data can be created using TexturePacker, see: Performance optimization for cocos2d-x using polygon sprite meshes

[zawasp]

Awesome, will test with the new beta TexturePacker (off-topic: does the 3.x license include an upgrade for 4.x?)

[CodeAndWeb]

@zawasp We don't care about major or minor releases. You get all released that are covered within your upgrade period. E.g. if you have upgrades included until 2015-12 you can use the current version.

[Yehsam23]

Does any other solution if i don't have TexturePacker v4 ? Maybe we need add generate SpriteFrame AutoPolygon method?

Thanks