From: Steinar H. Gunderson Date: Sun, 1 Nov 2015 01:09:56 +0000 (+0100) Subject: Add a function to let non-input effects override texture bounce. X-Git-Tag: 1.3.0~23 X-Git-Url: https://git.sesse.net/?a=commitdiff_plain;ds=sidebyside;h=6ec130490868eb8316cb2cdce9fbfd237d25a00e;p=movit Add a function to let non-input effects override texture bounce. Definitely read the comment before using; it is not for the faint of heart. Also make ResampleEffect tolerate this kind of abuse. --- diff --git a/effect.h b/effect.h index 6154dac..ebbb672 100644 --- a/effect.h +++ b/effect.h @@ -217,6 +217,20 @@ public: // and allow dependent effects to change that sampler state. virtual bool is_single_texture() const { return false; } + // If set, this effect should never be bounced to an output, even if a + // dependent effect demands texture bounce. + // + // Note that setting this can invoke undefined behavior, up to and including crashing, + // so you should only use it if you have deep understanding of your entire chain + // and Movit's processing of it. The most likely use case is if you have an input + // that's cheap to compute but not a single texture (e.g. YCbCrInput), and want + // to run a ResampleEffect directly from it. Normally, this would require a bounce, + // but it's faster not to. (However, also note that in this case, effective texel + // subpixel precision will be too optimistic, since chroma is already subsampled.) + // + // Has no effect if is_single_texture() is set. + virtual bool override_disable_bounce() const { return false; } + // If changes_output_size() is true, you must implement this to tell // the framework what output size you want. Also, you can set a // virtual width/height, which is the size the next effect (if any) diff --git a/effect_chain.cpp b/effect_chain.cpp index 4a333ea..3905564 100644 --- a/effect_chain.cpp +++ b/effect_chain.cpp @@ -184,6 +184,13 @@ GLenum EffectChain::get_input_sampler(Node *node, unsigned input_num) const return GL_TEXTURE0 + node->incoming_links[input_num]->bound_sampler_num; } +GLenum EffectChain::has_input_sampler(Node *node, unsigned input_num) const +{ + assert(input_num < node->incoming_links.size()); + return node->incoming_links[input_num]->bound_sampler_num >= 0 && + node->incoming_links[input_num]->bound_sampler_num < 8; +} + void EffectChain::find_all_nonlinear_inputs(Node *node, vector *nonlinear_inputs) { if (node->output_gamma_curve == GAMMA_LINEAR && @@ -500,7 +507,8 @@ Phase *EffectChain::construct_phase(Node *output, map *complete bool start_new_phase = false; if (node->effect->needs_texture_bounce() && - !deps[i]->effect->is_single_texture()) { + !deps[i]->effect->is_single_texture() && + !deps[i]->effect->override_disable_bounce()) { start_new_phase = true; } diff --git a/effect_chain.h b/effect_chain.h index 9fb1d4e..c3dadff 100644 --- a/effect_chain.h +++ b/effect_chain.h @@ -303,6 +303,13 @@ public: // single-sampler input, or from an RTT texture. GLenum get_input_sampler(Node *node, unsigned input_num) const; + // Whether input of corresponds to a single sampler + // (see get_input_sampler()). Normally, you should not need to call this; + // however, if the input Effect has set override_texture_bounce(), + // this will return false, and you could be flexible and check it first + // if you want. + GLenum has_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. // Any resources you get from the pool must be returned to the pool diff --git a/resample_effect.cpp b/resample_effect.cpp index 95f5575..a731568 100644 --- a/resample_effect.cpp +++ b/resample_effect.cpp @@ -717,10 +717,12 @@ void SingleResamplePassEffect::set_gl_state(GLuint glsl_program_num, const strin // We specifically do not want mipmaps on the input texture; // they break minification. Node *self = chain->find_node_for_effect(this); - glActiveTexture(chain->get_input_sampler(self, 0)); - check_error(); - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); - check_error(); + if (chain->has_input_sampler(self, 0)) { + glActiveTexture(chain->get_input_sampler(self, 0)); + check_error(); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); + check_error(); + } } } // namespace movit