opengl - 关于 GL_VERTEX_ARRAY 的一个问题

Question

这只是出于兴趣，但是 GL_VERTEX_ARRAY 将“保持”并通过 drawArrays() 之类的东西渲染的顶点数量是否有限制？或者理论上我可以通过几百万个顶点并且仍然能够调用 drawArrays() 吗？

Answer 1

自 OpenGL-1.2 以来，在使用 glDrawRangeElements 时存在一种限制:

Implementations denote recommended maximum amounts of vertex and index data, which may be queried by calling GetIntegerv with the symbolic constants MAX_ELEMENTS_VERTICES and MAX_ELEMENTS_INDICES. If end-start+1 is greater than the value of MAX_ELEMENTS_VERTICES, or if count is greater than the value of MAX_ELEMENTS_INDICES, then the call may operate at reduced performance. There is no requirement that all vertices in the range start; end be referenced. However, the implementation may partially process unused vertices, reducing performance from what could be achieved with an optimal index set.

但这更像是一个建议，而不是一个硬性约束。除此之外，真正的限制是安装的内存量，以及为索引元素数组选择的类型可以解决的问题

但是，glDrawRangeElements 的限制通常也可以很好地指示一般的批量大小。