bring old R_Shadow_ScissorForBBox code (new code still there, commented out), since...

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@10527 d7cf8633-e32d-0410-b094-e92efae38249
::stable-branch::merge=6aa5a03c470f7a0ee54459b3a9263b771626b8c4

diff --git a/r_shadow.c b/r_shadow.c
index eb571dd25ddbc5f82ffaa2d627e7ee9179eda6df..c8b914318a310edc01ce72d386a29d5626ac17a3 100644 (file)
--- a/r_shadow.c
+++ b/r_shadow.c
@@ -2427,8 +2427,161 @@ void R_Shadow_RenderMode_End(void)
        r_shadow_rendermode = R_SHADOW_RENDERMODE_NONE;
 }
 
+int bboxedges[12][2] =
+{
+       // top
+       {0, 1}, // +X
+       {0, 2}, // +Y
+       {1, 3}, // Y, +X
+       {2, 3}, // X, +Y
+       // bottom
+       {4, 5}, // +X
+       {4, 6}, // +Y
+       {5, 7}, // Y, +X
+       {6, 7}, // X, +Y
+       // verticals
+       {0, 4}, // +Z
+       {1, 5}, // X, +Z
+       {2, 6}, // Y, +Z
+       {3, 7}, // XY, +Z
+};
+
 qboolean R_Shadow_ScissorForBBox(const float *mins, const float *maxs)
 {
+       int i, ix1, iy1, ix2, iy2;
+       float x1, y1, x2, y2;
+       vec4_t v, v2;
+       float vertex[20][3];
+       int j, k;
+       vec4_t plane4f;
+       int numvertices;
+       float corner[8][4];
+       float dist[8];
+       int sign[8];
+       float f;
+
+       r_shadow_lightscissor[0] = r_refdef.view.viewport.x;
+       r_shadow_lightscissor[1] = r_refdef.view.viewport.y;
+       r_shadow_lightscissor[2] = r_refdef.view.viewport.width;
+       r_shadow_lightscissor[3] = r_refdef.view.viewport.height;
+
+       if (!r_shadow_scissor.integer)
+               return false;
+
+       // if view is inside the light box, just say yes it's visible
+       if (BoxesOverlap(r_refdef.view.origin, r_refdef.view.origin, mins, maxs))
+               return false;
+
+       x1 = y1 = x2 = y2 = 0;
+
+       // transform all corners that are infront of the nearclip plane
+       VectorNegate(r_refdef.view.frustum[4].normal, plane4f);
+       plane4f[3] = r_refdef.view.frustum[4].dist;
+       numvertices = 0;
+       for (i = 0;i < 8;i++)
+       {
+               Vector4Set(corner[i], (i & 1) ? maxs[0] : mins[0], (i & 2) ? maxs[1] : mins[1], (i & 4) ? maxs[2] : mins[2], 1);
+               dist[i] = DotProduct4(corner[i], plane4f);
+               sign[i] = dist[i] > 0;
+               if (!sign[i])
+               {
+                       VectorCopy(corner[i], vertex[numvertices]);
+                       numvertices++;
+               }
+       }
+       // if some points are behind the nearclip, add clipped edge points to make
+       // sure that the scissor boundary is complete
+       if (numvertices > 0 && numvertices < 8)
+       {
+               // add clipped edge points
+               for (i = 0;i < 12;i++)
+               {
+                       j = bboxedges[i][0];
+                       k = bboxedges[i][1];
+                       if (sign[j] != sign[k])
+                       {
+                               f = dist[j] / (dist[j] - dist[k]);
+                               VectorLerp(corner[j], f, corner[k], vertex[numvertices]);
+                               numvertices++;
+                       }
+               }
+       }
+
+       // if we have no points to check, the light is behind the view plane
+       if (!numvertices)
+               return true;
+
+       // if we have some points to transform, check what screen area is covered
+       x1 = y1 = x2 = y2 = 0;
+       v[3] = 1.0f;
+       //Con_Printf("%i vertices to transform...\n", numvertices);
+       for (i = 0;i < numvertices;i++)
+       {
+               VectorCopy(vertex[i], v);
+               R_Viewport_TransformToScreen(&r_refdef.view.viewport, v, v2);
+               //Con_Printf("%.3f %.3f %.3f %.3f transformed to %.3f %.3f %.3f %.3f\n", v[0], v[1], v[2], v[3], v2[0], v2[1], v2[2], v2[3]);
+               if (i)
+               {
+                       if (x1 > v2[0]) x1 = v2[0];
+                       if (x2 < v2[0]) x2 = v2[0];
+                       if (y1 > v2[1]) y1 = v2[1];
+                       if (y2 < v2[1]) y2 = v2[1];
+               }
+               else
+               {
+                       x1 = x2 = v2[0];
+                       y1 = y2 = v2[1];
+               }
+       }
+
+       // now convert the scissor rectangle to integer screen coordinates
+       ix1 = (int)(x1 - 1.0f);
+       //iy1 = vid.height - (int)(y2 - 1.0f);
+       //iy1 = r_refdef.view.viewport.width + 2 * r_refdef.view.viewport.x - (int)(y2 - 1.0f);
+       iy1 = (int)(y1 - 1.0f);
+       ix2 = (int)(x2 + 1.0f);
+       //iy2 = vid.height - (int)(y1 + 1.0f);
+       //iy2 = r_refdef.view.viewport.height + 2 * r_refdef.view.viewport.y - (int)(y1 + 1.0f);
+       iy2 = (int)(y2 + 1.0f);
+       //Con_Printf("%f %f %f %f\n", x1, y1, x2, y2);
+
+       // clamp it to the screen
+       if (ix1 < r_refdef.view.viewport.x) ix1 = r_refdef.view.viewport.x;
+       if (iy1 < r_refdef.view.viewport.y) iy1 = r_refdef.view.viewport.y;
+       if (ix2 > r_refdef.view.viewport.x + r_refdef.view.viewport.width) ix2 = r_refdef.view.viewport.x + r_refdef.view.viewport.width;
+       if (iy2 > r_refdef.view.viewport.y + r_refdef.view.viewport.height) iy2 = r_refdef.view.viewport.y + r_refdef.view.viewport.height;
+
+       // if it is inside out, it's not visible
+       if (ix2 <= ix1 || iy2 <= iy1)
+               return true;
+
+       // the light area is visible, set up the scissor rectangle
+       r_shadow_lightscissor[0] = ix1;
+       r_shadow_lightscissor[1] = iy1;
+       r_shadow_lightscissor[2] = ix2 - ix1;
+       r_shadow_lightscissor[3] = iy2 - iy1;
+
+       // D3D Y coordinate is top to bottom, OpenGL is bottom to top, fix the D3D one
+       switch(vid.renderpath)
+       {
+       case RENDERPATH_D3D9:
+       case RENDERPATH_D3D10:
+       case RENDERPATH_D3D11:
+               r_shadow_lightscissor[1] = vid.height - r_shadow_lightscissor[1] - r_shadow_lightscissor[3];
+               break;
+       case RENDERPATH_GL11:
+       case RENDERPATH_GL13:
+       case RENDERPATH_GL20:
+       case RENDERPATH_CGGL:
+               break;
+       }
+
+       r_refdef.stats.lights_scissored++;
+       return false;
+
+       /*
+       VorteX: originally written by divVerent, that code is broken on ATI
+
        if (!r_shadow_scissor.integer)
        {
                r_shadow_lightscissor[0] = r_refdef.view.viewport.x;
@@ -2437,7 +2590,6 @@ qboolean R_Shadow_ScissorForBBox(const float *mins, const float *maxs)
                r_shadow_lightscissor[3] = r_refdef.view.viewport.height;
                return false;
        }
-
        if(R_ScissorForBBox(mins, maxs, r_shadow_lightscissor))
        {
                if(r_shadow_lightscissor[0] != r_refdef.view.viewport.x
@@ -2449,6 +2601,7 @@ qboolean R_Shadow_ScissorForBBox(const float *mins, const float *maxs)
        }
        else
                return true; // invisible
+       */
 }
 
 static void R_Shadow_RenderLighting_Light_Vertex_Shading(int firstvertex, int numverts, int numtriangles, const int *element3i, const float *diffusecolor, const float *ambientcolor)