- ssgForceBasicState();
- glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
-}
-
-// Yanked from the YASim codebase. Should probably be replaced with
-// the 4x4 routine from plib, which is more appropriate here.
-static void invert33Matrix(float* m)
-{
- // Compute the inverse as the adjoint matrix times 1/(det M).
- // A, B ... I are the cofactors of a b c
- // d e f
- // g h i
- float a=m[0], b=m[1], c=m[2];
- float d=m[3], e=m[4], f=m[5];
- float g=m[6], h=m[7], i=m[8];
-
- float A = (e*i - h*f);
- float B = -(d*i - g*f);
- float C = (d*h - g*e);
- float D = -(b*i - h*c);
- float E = (a*i - g*c);
- float F = -(a*h - g*b);
- float G = (b*f - e*c);
- float H = -(a*f - d*c);
- float I = (a*e - d*b);
-
- float id = 1/(a*A + b*B + c*C);
-
- m[0] = id*A; m[1] = id*D; m[2] = id*G;
- m[3] = id*B; m[4] = id*E; m[5] = id*H;
- m[6] = id*C; m[7] = id*F; m[8] = id*I;
-}
-
-void
-FGPanel::setupVirtualCockpit()
-{
- int i;
- FGViewer* view = globals->get_current_view();
-
- // Corners for the panel quad. These numbers put a "standard"
- // panel at 1m from the eye, with a horizontal size of 60 degrees,
- // and with its center 5 degrees down. This will work well for
- // most typical screen-space panel definitions. In principle,
- // these should be settable per-panel, so that you can have lots
- // of panel objects plastered about the cockpit in realistic
- // positions and orientations.
- float DY = .0875; // tan(5 degrees)
- float a[] = { -0.5773503, -0.4330172 - DY, -1 }; // bottom left
- float b[] = { 0.5773503, -0.4330172 - DY, -1 }; // bottom right
- float c[] = { -0.5773503, 0.4330172 - DY, -1 }; // top left
-
- // A standard projection, in meters, with especially close clip
- // planes.
- glMatrixMode(GL_PROJECTION);
- glPushMatrix();
- glLoadIdentity();
- gluPerspective(view->get_v_fov(), 1/view->get_aspect_ratio(),
- 0.01, 100);
-
- glMatrixMode(GL_MODELVIEW);
- glPushMatrix();
-
- // Generate a "look at" matrix using OpenGL (!) coordinate
- // conventions.
- float lookat[3];
- float pitch = view->get_view_tilt();
- float rot = view->get_view_offset();
- lookat[0] = -sin(rot);
- lookat[1] = sin(pitch) / cos(pitch);
- lookat[2] = -cos(rot);
- if(fabs(lookat[1]) > 9999) lookat[1] = 9999; // FPU sanity
- gluLookAt(0, 0, 0, lookat[0], lookat[1], lookat[2], 0, 1, 0);
-
- // Translate the origin to the location of the panel quad
- glTranslatef(a[0], a[1], a[2]);
-
- // Generate a matrix to translate unit square coordinates from the
- // panel to real world coordinates. Use a basis for the panel
- // quad and invert. Note: this matrix is relatively expensive to
- // compute, and is invariant. Consider precomputing and storing
- // it. Also, consider using the plib vector math routines, so the
- // reuse junkies don't yell at me. (Fine, I hard-coded a cross
- // product. Just shoot me and be done with it.)
- float u[3], v[3], w[3], m[9];
- for(i=0; i<3; i++) u[i] = b[i] - a[i]; // U = B - A
- for(i=0; i<3; i++) v[i] = c[i] - a[i]; // V = C - A
- w[0] = u[1]*v[2] - v[1]*u[2]; // W = U x V
- w[1] = u[2]*v[0] - v[2]*u[0];
- w[2] = u[0]*v[1] - v[0]*u[1];
- for(int i=0; i<3; i++) { // |Ux Uy Uz|-1
- m[i] = u[i]; // m =|Vx Vy Vz|
- m[i+3] = v[i]; // |Wx Wy Wz|
- m[i+6] = w[i];
- }
- invert33Matrix(m);
-
- float glm[16]; // Expand to a 4x4 OpenGL matrix.
- glm[0] = m[0]; glm[4] = m[1]; glm[8] = m[2]; glm[12] = 0;
- glm[1] = m[3]; glm[5] = m[4]; glm[9] = m[5]; glm[13] = 0;
- glm[2] = m[6]; glm[6] = m[7]; glm[10] = m[8]; glm[14] = 0;
- glm[3] = 0; glm[7] = 0; glm[11] = 0; glm[15] = 1;
- glMultMatrixf(glm);
-
- // Finally, a scaling factor to convert the 1024x768 range the
- // panel uses to a unit square mapped to the panel quad.
- glScalef(1./1024, 1./768, 1);
-
- // Scale to the appropriate vertical size. I'm not quite clear on
- // this yet; an identical scaling is not appropriate for
- // _width, for example. This should probably go away when panel
- // coordinates get sanified for virtual cockpits.
- glScalef(1, _height/768.0, 1);
-
- // Now, turn off the Z buffer. The panel code doesn't need
- // it, and we're using different clip planes anyway (meaning we
- // can't share it without glDepthRange() hackery or much
- // framebuffer bandwidth wasteage)
- glDisable(GL_DEPTH_TEST);
-}