[virglrenderer-devel] [PATCH] vrend: specify correct offset in resource copy fallback path

[Gurchetan Singh]

glGetTexImage returns the entire texture, and we always copy from
the beginning of the texture. Instead, we should start copying
from the offset specified by the bounding box.

Fixes:
    dEQP-GLES3.functional.texture.shadow.2d_array.*.*depth*

Example test cases:
    dEQP-GLES3.functional.texture.shadow.2d_array.linear.not_equal_depth_component32f
    dEQP-GLES3.functional.texture.shadow.2d_array.nearest_mipmap_nearest.less_or_equal_depth_component16
    dEQP-GLES3.functional.texture.shadow.2d_array.nearest_mipmap_nearest.greater_or_equal_depth_component16

v2: Cubemap textures seem to suffer from the same issue:

Fixes:
   dEQP-GLES3.functional.texture.shadow.cube.nearest.*

Example test cases:
    dEQP-GLES3.functional.texture.shadow.cube.nearest.less_or_equal_depth_component16
    dEQP-GLES3.functional.texture.shadow.cube.nearest.less_or_equal_depth24_stencil8

v3: Make sure we still make only 1 glTexSubImage3D call in the non-cubemap case
---
 src/vrend_renderer.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/vrend_renderer.c b/src/vrend_renderer.c
index 68bc932..3496ebf 100644
--- a/src/vrend_renderer.c
+++ b/src/vrend_renderer.c
@@ -5737,8 +5737,10 @@ static void vrend_resource_copy_fallback(struct vrend_context *ctx,
    }
 
    glBindTexture(dst_res->target, dst_res->id);
-   slice_offset = 0;
-   for (i = 0; i < cube_slice; i++) {
+   slice_offset = dstz * slice_size;
+   cube_slice = (src_res->target == GL_TEXTURE_CUBE_MAP) ? dstz + src_box->depth : cube_slice;
+   i = (src_res->target == GL_TEXTURE_CUBE_MAP) ? dstz : 0;
+   for (; i < cube_slice; i++) {
       GLenum ctarget = dst_res->target == GL_TEXTURE_CUBE_MAP ? GL_TEXTURE_CUBE_MAP_POSITIVE_X + i : dst_res->target;
       if (compressed) {
          if (ctarget == GL_TEXTURE_1D) {
-- 
2.16.2.804.g6dcf76e118-goog