An apparatus and method for merging primitives and coordinating between vertex and ray transformations on a shared transformation unit. For example, one embodiment of a graphics processor comprises: a queue comprising a plurality of entries; ordering circuitry/logic to order triangles front to back within the queue; pairing circuitry/logic to identify triangles in the queue sharing an edge and to merge the triangles sharing an edge to produce merged triangle pairs; and shared transformation circuitry to alternate between performing vertex transformations on vertices of the merged triangle pairs and to performing ray transformations on ray direction/origin data.