A small handful of minor changes to the sliced texture transfer code and related functions

Nothing substantial to see here, I was originally planning on rewriting the sliced texture code to also handle misaligned formats, but this turns out to be a lot trickier to get right than I thought, and I'd rather avoid breaking everything right now.

src/gpu/utils.c

@@ -143,6 +143,10 @@ pl_gpu pl_gpu_finalize(struct pl_gpu_t *gpu)
     // Verification
     pl_assert(gpu->limits.max_tex_2d_dim);
     pl_assert(gpu->limits.max_variable_comps || gpu->limits.max_ubo_size);
+    pl_assert(gpu->limits.max_ubo_size    <= gpu->limits.max_buf_size);
+    pl_assert(gpu->limits.max_ssbo_size   <= gpu->limits.max_buf_size);
+    pl_assert(gpu->limits.max_vbo_size    <= gpu->limits.max_buf_size);
+    pl_assert(gpu->limits.max_mapped_size <= gpu->limits.max_buf_size);
 
     for (int n = 0; n < gpu->num_formats; n++) {
         pl_fmt fmt = gpu->formats[n];
@@ -466,18 +470,14 @@ int pl_tex_transfer_slices(pl_gpu gpu, pl_fmt texel_fmt,
                            struct pl_tex_transfer_params **out_slices)
 {
     PL_ARRAY(struct pl_tex_transfer_params) slices = {0};
-    size_t max_size = gpu->limits.max_ssbo_size;
+    size_t max_size = params->buf ? gpu->limits.max_buf_size : SIZE_MAX;
 
     pl_fmt fmt = params->tex->params.format;
-    if (fmt->emulated) {
-        pl_assert(texel_fmt);
+    if (fmt->emulated && texel_fmt) {
         size_t max_texel = gpu->limits.max_buffer_texels * texel_fmt->texel_size;
-        max_size = PL_MIN(max_size, max_texel);
+        max_size = PL_MIN(gpu->limits.max_ssbo_size, max_texel);
     }
 
-    if (max_size < fmt->texel_size)
-        return 0;
-
     int slice_w = pl_rect_w(params->rc);
     int slice_h = pl_rect_h(params->rc);
     int slice_d = pl_rect_d(params->rc);