Formalize the notion of messing with sampler state.

[movit] / effect_chain.h

diff --git a/effect_chain.h b/effect_chain.h
index 642f079201f037219b1ead3c02aebf3e85bfb28d..4417de912f9f979a8308f96e6291246c3c73841c 100644 (file)
--- a/effect_chain.h
+++ b/effect_chain.h
@@ -71,6 +71,15 @@ private:
        // phases as inputs, instead of Node.
        Phase *phase;
 
+       // If the effect has is_single_texture(), or if the output went to RTT
+       // and that texture has been bound to a sampler, the sampler number
+       // will be stored here.
+       //
+       // TODO: Can an RTT texture be used as inputs to multiple effects
+       // within the same phase? If so, we have a problem with modifying
+       // sampler state here.
+       int bound_sampler_num;
+
        // Used during the building of the effect chain.
        Colorspace output_color_space;
        GammaCurve output_gamma_curve;
@@ -173,6 +182,16 @@ public:
        void replace_receiver(Node *old_receiver, Node *new_receiver);
        void replace_sender(Node *new_sender, Node *receiver);
        void insert_node_between(Node *sender, Node *middle, Node *receiver);
+       Node *find_node_for_effect(Effect *effect) { return node_map[effect]; }
+
+       // Get the OpenGL sampler (GL_TEXTURE0, GL_TEXTURE1, etc.) for the
+       // input of the given node, so that one can modify the sampler state
+       // directly. Only valid to call during set_gl_state().
+       //
+       // Also, for this to be allowed, <node>'s effect must have
+       // needs_texture_bounce() set, so that it samples directly from a
+       // single-sampler input, or from an RTT texture.
+       GLenum get_input_sampler(Node *node, unsigned input_num) const;
 
        // Get the current resource pool assigned to this EffectChain.
        // Primarily to let effects allocate textures as needed.