Multiple skshapenode in one draw?

Question

Hi I have drawn skshapenodes connecting the nodes in my graph for my visual a* representation.

for(int x=0; x<64; x++)
        {
            for(int y=0; y<48; y++)
            {
                PathFindingNode *node = [[gridToDraw objectAtIndex:x] objectAtIndex:y];
                for(int i=0; i< node.connections.count; i++)
                {
                    PathFindingNode *neighbor = [node.connections objectAtIndex:i];

                    SKShapeNode *line = [SKShapeNode node];
                    CGMutablePathRef pathToDraw = CGPathCreateMutable();
                    CGPathMoveToPoint(pathToDraw, NULL, node.position.x, node.position.y);
                    CGPathAddLineToPoint(pathToDraw, NULL, neighbor.position.x, neighbor.position.y);
                    line.path = pathToDraw;
                    line.lineWidth = 0.1f;
                    [line setStrokeColor:[UIColor blueColor]];
                    line.alpha = 0.1f;
                    [self addChild:line];
                }
            }
        }

There are lots of nodes in my graph and this draws almost 22,000 shapes. Is there a way I can draw these shapes in one draw call, as they are all the same, the only difference is the start and end location of them.

If I used a texture instead, which would be loaded in once, how could I change the rotation of it to join all of my nodes up like above.

Regards,

UPDATE:

SKShapeNode *line = [SKShapeNode node];
        CGMutablePathRef pathToDraw = CGPathCreateMutable();

        for(int x=0; x<64; x++)
        {
            for(int y=0; y<48; y++)
            {
                PathFindingNode *node = [[gridToDraw objectAtIndex:x] objectAtIndex:y];
                for(int i=0; i< node.connections.count; i++)
                {
                    PathFindingNode *neighbor = [node.connections objectAtIndex:i];
                    CGPathMoveToPoint(pathToDraw, NULL, node.position.x, node.position.y);
                    CGPathAddLineToPoint(pathToDraw, NULL, neighbor.position.x, neighbor.position.y);
                }
            }
        }

        line.path = pathToDraw;
        line.lineWidth = 0.1f;
        [line setStrokeColor:[UIColor blueColor]];
        line.alpha = 0.1f;
        [self addChild:line];

I have updated my code to look like the above, this draws one sknode, but it draws 185 times, why is this?

Answer 1

I was going to answer this yesterday on a similar question but it disappeared.

You can create one path and draw everything as one SKShapeNode using CGPathAddPath to merge the paths as you go.

Here's an example :

SKEffectNode *effectNode = [[SKEffectNode alloc]init];
SKShapeNode  *shape = [[SKShapeNode alloc] init];
CGMutablePathRef myPath = CGPathCreateMutable();
CGPathAddArc(myPath, NULL, 0,0, 15, 0, M_PI*2, YES);

CGMutablePathRef pathTwo = CGPathCreateMutable();
CGPathAddArc(pathTwo, NULL, 50,0, 15, 0, M_PI*2, YES);     
CGPathAddPath(myPath, NULL, pathTwo);

CGMutablePathRef pathThree = CGPathCreateMutable();
CGPathAddArc(pathThree, NULL, 100,0, 15, 0, M_PI*2, YES);
CGPathAddPath(myPath, NULL, pathThree);

shape.path = myPath;

[effectNode addChild:shape];
[self addChild:effectNode];

effectNode.shouldRasterize = YES;  // if you don't rasterize it's horrifically slow.

This was just an example of how to merge the different paths to create one SKShapeNode that has all visual elements you are seeking. You'll need to apply this concept to your code.

I added the resulting SKShapeNode to an SKEffectNode so that I could utilize the shouldRasterize property to cache the shape, otherwise your framerate will be horrible.