Package org.oscim.renderer.bucket

Class LineTexBucket

java.lang.Object
org.oscim.utils.pool.Inlist<RenderBucket>
org.oscim.renderer.bucket.RenderBucket
org.oscim.renderer.bucket.LineBucket
org.oscim.renderer.bucket.LineTexBucket
public final class LineTexBucket extends LineBucket
RenderElement for textured or stippled lines

Interleave two segment quads in one block to be able to use vertices twice. pos0 and pos1 use the same vertex array where pos1 has an offset of one vertex. The vertex shader will use pos0 when the vertexId is even, pos1 when the Id is odd.

As there is no gl_VertexId in gles 2.0 an additional 'flip' array is used. Depending on 'flip' extrusion is inverted.

Indices and flip buffers can be static. 

 First pass: using even vertex array positions
   (used vertices are in braces)
 vertex id   0  1  2  3  4  5  6  7
 pos0     x (0) 1 (2) 3 (4) 5 (6) 7 x
 pos1        x (0) 1 (2) 3 (4) 5 (6) 7 x
 flip        0  1  0  1  0  1  0  1

 Second pass: using odd vertex array positions
 vertex id   0  1  2  3  4  5  6  7
 pos0   x 0 (1) 2 (3) 4 (5) 6 (7) x
 pos1      x 0 (1) 2 (3) 4 (5) 6 (7) x
 flip        0  1  0  1  0  1  0  1

Vertex layout (here: 1 unit == 1 short): [2 unit] position, [2 unit] extrusion, [1 unit] line length [1 unit] unused

indices, for two blocks: 0, 1, 2, 2, 1, 3, 4, 5, 6, 6, 5, 7,

BIG NOTE: renderer assumes to be able to offset vertex array position so that in the first pass 'pos1' offset will be < 0 if no data precedes - in our case there is always the polygon fill array at start - see addLine hack otherwise.

  • Field Details

    • evenQuads

      public int evenQuads

    • oddQuads

      public int oddQuads

  • Method Details