# OpenGL Mouse to World Coordinates / python

I have been stuck for a few days now. I saw all the sources I could find and tried a more than one technique. Anyway here is my code (gathered from a few places) the closes Ive gotten is close to the mouse cursor but not quite there

``````	x, y = pygame.mouse.get_pos()

model_view = np.array(glGetDoublev(GL_MODELVIEW_MATRIX))
proj = np.array(glGetDoublev(GL_PROJECTION_MATRIX))
view = np.array(glGetIntegerv(GL_VIEWPORT))
corrected_y = view-y
corrected_x = x

glEnable(GL_DEPTH_TEST)
depth = glReadPixels(x, corrected_y, 1, 1, GL_DEPTH_COMPONENT, GL_FLOAT)
print (depth)

pointa = np.array(gluUnProject(corrected_x, corrected_y, -1))
originalpt = np.array(gluUnProject(corrected_x, corrected_y, 1, model_view, proj,view))
print (originalpt, " original pt")

print("pointa", pointa,"  originalpt",originalpt)
ray = originalpt - pointa
raydirection = np.linalg.norm(ray)
print (raydirection, "ray dir")
print("ray", ray)
normal = np.array([0.00,1.00,0.00,])
(originalpt*normal))/((normal*pointa)+(normal*pointa)+(normal*pointa)))
t = -((normal.dot(originalpt)+1)/normal.dot(raydirection)+1)
#point = originalpt+ raydirection*t
point = originalpt + (t*raydirection)
print("tttt", t)

print(point,"point intrs")
mylist.append(point)

``````

please not this is not the best version of the code. there was a better version that got me closer, by changing the equation of point to = originalpt + t* pointa

Pass the value from the depth buffer as the third parameter (`winZ`) to `gluUnProject`.

Also: the `winX`/`winY` parameters should normally be:

``````	corrected_x = x + 0.5
corrected_y = view - y - 0.5
``````

as those are the window coordinates of the centre of the pixel containing the mouse cursor, rather than the top-left corner. The values in the depth buffer are obtained by interpolating the triangle at the centre of each pixel.

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