+ bool all_ok = true;
+ for (unsigned i = 0; i < nonlinear_inputs.size(); ++i) {
+ Input *input = static_cast<Input *>(nonlinear_inputs[i]->effect);
+ all_ok &= input->can_output_linear_gamma();
+ }
+
+ if (!all_ok) {
+ continue;
+ }
+
+ for (unsigned i = 0; i < nonlinear_inputs.size(); ++i) {
+ nonlinear_inputs[i]->effect->set_int("output_linear_gamma", 1);
+ nonlinear_inputs[i]->output_gamma_curve = GAMMA_LINEAR;
+ }
+
+ // Re-sort topologically, and propagate the new information.
+ propagate_gamma_and_color_space();
+
+ found_any = true;
+ break;
+ }
+
+ char filename[256];
+ sprintf(filename, "step%u-gammafix-iter%u.dot", step, ++gamma_propagation_pass);
+ output_dot(filename);
+ assert(gamma_propagation_pass < 100);
+ } while (found_any);
+}
+
+void EffectChain::fix_internal_gamma_by_inserting_nodes(unsigned step)
+{
+ unsigned gamma_propagation_pass = 0;
+ bool found_any;
+ do {
+ found_any = false;
+ for (unsigned i = 0; i < nodes.size(); ++i) {
+ Node *node = nodes[i];
+ if (!node_needs_gamma_fix(node)) {
+ continue;
+ }
+
+ // Go through each input that is not linear gamma, and insert
+ // a gamma conversion before it.
+ for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
+ Node *input = node->incoming_links[j];
+ assert(input->output_gamma_curve != GAMMA_INVALID);
+ if (input->output_gamma_curve == GAMMA_LINEAR) {
+ continue;
+ }
+ Node *conversion = add_node(new GammaExpansionEffect());
+ conversion->effect->set_int("destination_curve", GAMMA_LINEAR);
+ conversion->output_gamma_curve = GAMMA_LINEAR;
+ insert_node_between(input, conversion, node);
+ }
+
+ // Re-sort topologically, and propagate the new information.
+ propagate_gamma_and_color_space();
+
+ found_any = true;
+ break;
+ }
+
+ char filename[256];
+ sprintf(filename, "step%u-gammafix-iter%u.dot", step, ++gamma_propagation_pass);
+ output_dot(filename);
+ assert(gamma_propagation_pass < 100);
+ } while (found_any);
+
+ for (unsigned i = 0; i < nodes.size(); ++i) {
+ Node *node = nodes[i];
+ if (node->disabled) {
+ continue;
+ }
+ assert(node->output_gamma_curve != GAMMA_INVALID);
+ }
+}
+
+// Make so that the output is in the desired gamma.
+// Note that this assumes linear input gamma, so it might create the need
+// for another pass of fix_internal_gamma().
+void EffectChain::fix_output_gamma()
+{
+ Node *output = find_output_node();
+ if (output->output_gamma_curve != output_format.gamma_curve) {
+ Node *conversion = add_node(new GammaCompressionEffect());
+ conversion->effect->set_int("destination_curve", output_format.gamma_curve);
+ conversion->output_gamma_curve = output_format.gamma_curve;
+ connect_nodes(output, conversion);
+ }
+}
+
+// Find the output node. This is, simply, one that has no outgoing links.
+// If there are multiple ones, the graph is malformed (we do not support
+// multiple outputs right now).
+Node *EffectChain::find_output_node()
+{
+ std::vector<Node *> output_nodes;
+ for (unsigned i = 0; i < nodes.size(); ++i) {
+ Node *node = nodes[i];
+ if (node->disabled) {
+ continue;
+ }
+ if (node->outgoing_links.empty()) {
+ output_nodes.push_back(node);
+ }
+ }
+ assert(output_nodes.size() == 1);
+ return output_nodes[0];
+}
+
+void EffectChain::finalize()
+{
+ // Output the graph as it is before we do any conversions on it.
+ output_dot("step0-start.dot");
+
+ // Give each effect in turn a chance to rewrite its own part of the graph.
+ // Note that if more effects are added as part of this, they will be
+ // picked up as part of the same for loop, since they are added at the end.
+ for (unsigned i = 0; i < nodes.size(); ++i) {
+ nodes[i]->effect->rewrite_graph(this, nodes[i]);
+ }
+ output_dot("step1-rewritten.dot");
+
+ propagate_gamma_and_color_space();
+ output_dot("step2-propagated.dot");
+
+ fix_internal_color_spaces();
+ fix_output_color_space();
+ output_dot("step4-output-colorspacefix.dot");
+
+ // Note that we need to fix gamma after colorspace conversion,
+ // because colorspace conversions might create needs for gamma conversions.
+ // Also, we need to run an extra pass of fix_internal_gamma() after
+ // fixing the output gamma, as we only have conversions to/from linear.
+ fix_internal_gamma_by_asking_inputs(5);
+ fix_internal_gamma_by_inserting_nodes(6);
+ fix_output_gamma();
+ output_dot("step8-output-gammafix.dot");
+ fix_internal_gamma_by_asking_inputs(9);
+ fix_internal_gamma_by_inserting_nodes(10);
+
+ output_dot("step11-final.dot");
+