Previously the function containing the default texture lookup is
always generated regardless of whether there is a snippet with a
replace string which would cause it not be used. Now this snippets are
all scanned to check for replace strings before generating the texture
lookup.
Reviewed-by: Robert Bragg <robert@linux.intel.com>
The loop that generates code for a list of snippets now starts from
the first snippet that has a replace string. Any snippets before that
would be ignored so there's no point in generating code for them.
Reviewed-by: Robert Bragg <robert@linux.intel.com>
Instead of specifying the hook point when adding to the pipeline using
a separate function for each hook, the hook is now a property of the
snippet. The hook is set on construction and is then read-only.
Reviewed-by: Robert Bragg <robert@linux.intel.com>
This adds a per-layer snippet hook for the texure lookup. Here the
snippet can modify the texture coordinates used for the lookup or
modify the texel resulting from the lookup. This is the first
per-layer hook so this also adds the
COGL_PIPELINE_LAYER_STATE_FRAGMENT_SNIPPETS state and all of the
boilerplate needed to make that work.
Most of the functions used by the pipeline state to manage the snippet
list has been moved into cogl-pipeline-snippet.c so that it can be
shared with the layer state.
Reviewed-by: Robert Bragg <robert@linux.intel.com>
If present, the 'replace' string will be used instead of whatever code
would normally be invoked for that hook point. It will also replace
any previous snippets.
Reviewed-by: Robert Bragg <robert@linux.intel.com>
Each snippet is now given its own function which contains the pre and
post strings. Between these strings the function will chain on to
another function. The generated cogl source is now stored in a
function called cogl_generated_source() which the last snippet will
chain on to. This should make it so that each snippet has its own
namespace for local variables and it can share variables declared in
the pre string in the post string. Hopefully the GLSL compiler will
just inline all of the functions so it shouldn't make much difference
to the compiled output.
Reviewed-by: Robert Bragg <robert@linux.intel.com>
