Function reglElements

lib/elements.js:172–253

(options)

    stats.elementsCount++

    function reglElements (options) {
      if (!options) {
        buffer()
        elements.primType = GL_TRIANGLES
        elements.vertCount = 0
        elements.type = GL_UNSIGNED_BYTE
      } else if (typeof options === 'number') {
        buffer(options)
        elements.primType = GL_TRIANGLES
        elements.vertCount = options | 0
        elements.type = GL_UNSIGNED_BYTE
      } else {
        var data = null
        var usage = GL_STATIC_DRAW
        var primType = -1
        var vertCount = -1
        var byteLength = 0
        var dtype = 0
        if (Array.isArray(options) ||
            isTypedArray(options) ||
            isNDArrayLike(options)) {
          data = options
        } else {
          check.type(options, 'object', 'invalid arguments for elements')
          if ('data' in options) {
            data = options.data
            check(
              Array.isArray(data) ||
                isTypedArray(data) ||
                isNDArrayLike(data),
              'invalid data for element buffer')
          }
          if ('usage' in options) {
            check.parameter(
              options.usage,
              usageTypes,
              'invalid element buffer usage')
            usage = usageTypes[options.usage]
          }
          if ('primitive' in options) {
            check.parameter(
              options.primitive,
              primTypes,
              'invalid element buffer primitive')
            primType = primTypes[options.primitive]
          }
          if ('count' in options) {
            check(
              typeof options.count === 'number' && options.count >= 0,
              'invalid vertex count for elements')
            vertCount = options.count | 0
          }
          if ('type' in options) {
            check.parameter(
              options.type,
              elementTypes,
              'invalid buffer type')
            dtype = elementTypes[options.type]