diff options
Diffstat (limited to 'src/mesa/state_tracker/st_pbo.c')
| -rw-r--r-- | src/mesa/state_tracker/st_pbo.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/src/mesa/state_tracker/st_pbo.c b/src/mesa/state_tracker/st_pbo.c index f8787148ea6..ca6bdea1b66 100644 --- a/src/mesa/state_tracker/st_pbo.c +++ b/src/mesa/state_tracker/st_pbo.c @@ -153,6 +153,22 @@ st_pbo_addresses_pixelstore(struct st_context *st, return true; } +/* For download from a framebuffer, we may have to invert the Y axis. The + * setup is as follows: + * - set viewport to inverted, so that the position sysval is correct for + * texel fetches + * - this function adjusts the fragment shader's constant buffer to compute + * the correct destination addresses. + */ +void +st_pbo_addresses_invert_y(struct st_pbo_addresses *addr, + unsigned viewport_height) +{ + addr->constants.xoffset += + (viewport_height - 1 + 2 * addr->constants.yoffset) * addr->constants.stride; + addr->constants.stride = -addr->constants.stride; +} + /* Setup all vertex pipeline state, rasterizer state, and fragment shader * constants, and issue the draw call for PBO upload/download. * @@ -530,6 +546,7 @@ st_init_pbo_helpers(struct st_context *st) st->pbo.download_enabled = st->pbo.upload_enabled && + screen->get_param(screen, PIPE_CAP_SAMPLER_VIEW_TARGET) && screen->get_param(screen, PIPE_CAP_FRAMEBUFFER_NO_ATTACHMENT) && screen->get_shader_param(screen, PIPE_SHADER_FRAGMENT, PIPE_SHADER_CAP_MAX_SHADER_IMAGES) >= 1; |