This patch implements functionality of glDrawArraysInstancedBaseInstanceANGLE,
glDrawElementsInstancedBaseVertexBaseInstanceANGLE,
glMultiDrawArraysInstancedBaseInstanceANGLE,
and glMultiDrawElementsInstancedBaseVertexBaseInstanceANGLE
Workaround for OpenGL driver on Mac:
gl_VertexID on Mac with AMD GPU doesn't include baseVertex value.
So replace gl_VertexID with (gl_VertexID + angle_BaseVertex) if any.
Workaround for Vulkan GLSL:
gl_InstanceIndex on Vulkan includes baseInstance. So replace
gl_InstanceIndex with (gl_InstanceIndex - angle_BaseInstance) when
angle_BaseInstance is declared.
Bug: chromium:891861, angleproject:3402
Change-Id: Ia1d94b5d4d7da7e635468c05c962c4f7eb1b1919
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1750126
Commit-Queue: Shrek Shao <shrekshao@google.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
