Consider a triangular face of three vertices A(0,2,-1), B(1,0,1) and the origin O, and the normal vectors at the vertices are nA=(0,1,0), nB=(1,0,0) and nO=(0,0,1), respectively. The incident light is white and directional in direction of L=(1,2,2) and the intensity is 1, the background ambient light intensity is 0.1, and the diffuse reflection coefficients for (red, green, blue) are (0.6,0.7,0.8). No specular light contribution needs to be considered.Find the (red, green, blue) intensity values at the centre of the face using Gouraud shading.I do not know how to answer this question and have looked at my lecture slides, youtube videos, computer graphics textbook by Foley and Van Damm and obviously used google. Any help would be much appreciated. Edit: I want to find the intensity values using Gouraud shading, not flat shading. From my understanding, the intensity at a point is interpolated along polygon edges and scan lines? But with the information I am given in the question, I don't have a clue how to answer this question. This video helped a bit: https://www.youtube.com/watch?v=_SuyLrU2Xr0&t=142s but it doesn't set me up for answering this question.
Find RGB intensity values at center of face using Gouraud shading
rendering