Fix T66937: Blank view on navigation with auto-deph & large clip-end

2 files changed, 15 insertions, 11 deletions

diff --git a/source/blender/gpu/GPU_matrix.h b/source/blender/gpu/GPU_matrix.h
index 56d640ea0e4..eabfb5d2dc3 100644
--- a/source/blender/gpu/GPU_matrix.h
+++ b/source/blender/gpu/GPU_matrix.h
@@ -102,11 +102,15 @@ struct GPUMatrixUnproject_Precalc {
   float model_inverted[4][4];
   float view[4];
   bool is_persp;
-  /** Result of 'projmat_dimensions'. */
+  /**
+   * Result of #projmat_dimensions_db.
+   * Using double precision here is important as far clipping ranges
+   * can cause divide-by-zero when using float, see: T66937.
+   */
   struct {
-    float xmin, xmax;
-    float ymin, ymax;
-    float zmin, zmax;
+    double xmin, xmax;
+    double ymin, ymax;
+    double zmin, zmax;
   } dims;
 };
 
diff --git a/source/blender/gpu/intern/gpu_matrix.c b/source/blender/gpu/intern/gpu_matrix.c
index d0f7eab32a3..669bf56b726 100644
--- a/source/blender/gpu/intern/gpu_matrix.c
+++ b/source/blender/gpu/intern/gpu_matrix.c
@@ -536,13 +536,13 @@ bool GPU_matrix_unproject_precalc(struct GPUMatrixUnproject_Precalc *precalc,
                                   const int view[4])
 {
   precalc->is_persp = proj[3][3] == 0.0f;
-  projmat_dimensions(proj,
-                     &precalc->dims.xmin,
-                     &precalc->dims.xmax,
-                     &precalc->dims.ymin,
-                     &precalc->dims.ymax,
-                     &precalc->dims.zmin,
-                     &precalc->dims.zmax);
+  projmat_dimensions_db(proj,
+                        &precalc->dims.xmin,
+                        &precalc->dims.xmax,
+                        &precalc->dims.ymin,
+                        &precalc->dims.ymax,
+                        &precalc->dims.zmin,
+                        &precalc->dims.zmax);
   if (isinf(precalc->dims.zmax)) {
     /* We cannot retrieve the actual value of the clip_end.
      * Use `FLT_MAX` to avoid nans. */