opengl es - How can I calculate uv coordinates for vertices if I know the vertex coordinate of my texture on a plane -

i'm trying map texture on plane, know vertex coordinates texture, , coordinates 4 vertices. how can calculate uv texture coordinates 4 vertices?

here's picture show i'm trying do,

the yellow grid area texture, square texture skewed shape. green area plane want map texture on to. know vertex coordinates point a, b, c, d, , point 1, 2, 3, 4.

for example, if texture placed this

those vertex coordinates points. uv coordinates point a, b, c, d should (-0.5f, -0.5f), (1.5f, -0.5f), (1.5f, 1.5f), (-0.5f, 1.5f)

but if texture skewed first picture, how can calculate uv coordinates point a, b, c, d?

where trying cpu or gpu? assuming cpu project vertices of skewed plane onto green plane. if think of green plane screen has camera , therefore associated view , projection matrices project each point onto surface , find distance origin in case in middle of green plane.

from tags looks using opengl es, using fixed function or shaders? maths library use? glm has glm::project , glm::unproject want here's link info that.

here's general information on want do, want project 3d 2d , find relative distances on plane.

hope helps.