Do some more cleanups in anticipation of more flexible compute shader outputs.

[movit] / effect_chain.h

diff --git a/effect_chain.h b/effect_chain.h
index 54cf0e5d88869aec8e7e8e812bb0f4a44ec6797e..ee387a954613edc8629b49762d720e339479d9ab 100644 (file)
--- a/effect_chain.h
+++ b/effect_chain.h
@@ -195,15 +195,15 @@ struct Phase {
        std::map<Node *, std::string> effect_ids;
 
        // Uniforms for this phase; combined from all the effects.
-       std::vector<Uniform<int> > uniforms_image2d;
-       std::vector<Uniform<int> > uniforms_sampler2d;
-       std::vector<Uniform<bool> > uniforms_bool;
-       std::vector<Uniform<int> > uniforms_int;
-       std::vector<Uniform<float> > uniforms_float;
-       std::vector<Uniform<float> > uniforms_vec2;
-       std::vector<Uniform<float> > uniforms_vec3;
-       std::vector<Uniform<float> > uniforms_vec4;
-       std::vector<Uniform<Eigen::Matrix3d> > uniforms_mat3;
+       std::vector<Uniform<int>> uniforms_image2d;
+       std::vector<Uniform<int>> uniforms_sampler2d;
+       std::vector<Uniform<bool>> uniforms_bool;
+       std::vector<Uniform<int>> uniforms_int;
+       std::vector<Uniform<float>> uniforms_float;
+       std::vector<Uniform<float>> uniforms_vec2;
+       std::vector<Uniform<float>> uniforms_vec3;
+       std::vector<Uniform<float>> uniforms_vec4;
+       std::vector<Uniform<Eigen::Matrix3d>> uniforms_mat3;
 
        // For measurement of GPU time used.
        std::list<GLuint> timer_query_objects_running;
@@ -389,6 +389,22 @@ public:
        // the current viewport.
        void render_to_fbo(GLuint fbo, unsigned width, unsigned height);
 
+       // Render the effect chain to the given set of textures. This is equivalent
+       // to render_to_fbo() with a freshly created FBO bound to the given textures,
+       // except that it is more efficient if the last phase contains a compute shader.
+       // Thus, prefer this to render_to_fbo() where possible.
+       //
+       // The format must currently be GL_RGBA16F, and only one destination
+       // texture is supported. Both of these restrictions will be lifted in the future.
+       //
+       // All destination textures must be exactly of size <width> x <height>.
+       // width and height can not be zero.
+       struct DestinationTexture {
+               GLuint texnum;
+               GLenum format;
+       };
+       void render_to_texture(const std::vector<DestinationTexture> &destinations, unsigned width, unsigned height);
+
        Effect *last_added_effect() {
                if (nodes.empty()) {
                        return nullptr;
@@ -457,9 +473,19 @@ private:
        // as the last effect. Also pushes all phases in order onto <phases>.
        Phase *construct_phase(Node *output, std::map<Node *, Phase *> *completed_effects);
 
+       // Do the actual rendering of the chain. If <dest_fbo> is not (GLuint)-1,
+       // renders to that FBO. If <destinations> is non-empty, render to that set
+       // of textures (last phase, save for the dummy phase, must be a compute shader),
+       // with x/y ignored. Having both set is an error.
+       void render(GLuint dest_fbo, const std::vector<DestinationTexture> &destinations,
+                   unsigned x, unsigned y, unsigned width, unsigned height);
+
        // Execute one phase, ie. set up all inputs, effects and outputs, and render the quad.
-       void execute_phase(Phase *phase, bool last_phase,
-                          std::map<Phase *, GLuint> *output_textures,
+       // If dest_texture is 0, uses whatever output is current (and the phase must not be
+       // a compute shader).
+       void execute_phase(Phase *phase,
+                          const std::map<Phase *, GLuint> &output_textures,
+                          GLuint dest_texture,
                           std::set<Phase *> *generated_mipmaps);
 
        // Set up uniforms for one phase. The program must already be bound.
@@ -539,6 +565,12 @@ private:
        bool finalized;
        GLuint vbo;  // Contains vertex and texture coordinate data.
 
+       // Whether the last effect (which will then be in a phase all by itself)
+       // is a dummy effect that is only added because the last phase uses a compute
+       // shader, which cannot output directly to the backbuffer. This means that
+       // the phase can be skipped if we are _not_ rendering to the backbuffer.
+       bool has_dummy_effect = false;
+
        ResourcePool *resource_pool;
        bool owns_resource_pool;