drawing - webGL : draw two separate rect with one buffer -

my problem simple, build array 2 square coord :

var vertices = [  -64, -32, 0.0,                64, -32, 0.0,                 64,  32, 0.0,                -64, -32, 0.0,                -64, 32, 0.0,                 64, 32, 0.0 ];  vertices.push( -64 + 200, -32, 0.0,                 64 + 200, -32, 0.0,                  64 + 200, 32, 0.0,                 -64 + 200, -32, 0.0,                 -64 + 200, 32, 0.0,                  64 + 200, 32, 0.0 ); 

but resulting drawing looks :

expected result should 2 separate rect black color between them. , don't understand behavior.

when using triangle strips vertices implicitly indexed:

draws series of triangles (three-sided polygons) using vertices v0, v1, v2, v2, v1, v3 (note order), v2, v3, v4, , on. ordering ensure triangles drawn same orientation strip can correctly form part of surface.

if 1 want have separate triangles using triangle strips, 1 need add "stop vertices" generate degenerated triangle.

read answer explanation(with images) of triangle_strip , triangle_fan.

however triangle strips(and fans) can quite cumbersome work if you're not planning explicitly build strips or fans. , looking @ vertex layout i'm assuming want use plain triangles render geometry.