// Keeps the type of alpha (premultiplied, postmultiplied, blank)
// unchanged from input to output. Usually appropriate if you
// process all color channels in a linear fashion, do not change
- // alpha, and do not produce any new pixels thare have alpha != 1.0.
+ // alpha, and do not produce any new pixels that have alpha != 1.0.
//
// Does not make sense for inputs.
DONT_CARE_ALPHA_TYPE,
// set sets_virtual_output_size(), though.
//
// Does not make a lot of sense together with needs_texture_bounce().
- virtual bool one_to_one_sampling() const { return false; }
+ // Cannot be set for compute shaders.
+ virtual bool one_to_one_sampling() const { return strong_one_to_one_sampling(); }
+
+ // Similar in use to one_to_one_sampling(), but even stricter:
+ // The effect must not use texture coordinate in any way beyond
+ // giving it unmodified to its (single) input. This allows it to
+ // also be used after a compute shader, in the same phase.
+ //
+ // An effect that it strong one-to-one must also be one-to-one.
+ virtual bool strong_one_to_one_sampling() const { return false; }
// Whether this effect wants to output to a different size than
// its input(s) (see inform_input_size(), below). See also
assert(false);
}
+ // Whether this effect uses a compute shader instead of a regular fragment shader.
+ // Compute shaders are more flexible in that they can have multiple outputs
+ // for each invocation and also communicate between instances (by using shared
+ // memory within each group), but are not universally supported. The typical
+ // pattern would be to check movit_compute_shaders_supported and rewrite the
+ // graph to use a compute shader effect instead of a regular effect if it is
+ // available, in order to get better performance. Since compute shaders can reuse
+ // loads (again typically through shared memory), using needs_texture_bounce()
+ // is usually not needed, although it is allowed; the best candidates for compute
+ // shaders are typically those that sample many times from their input
+ // but can reuse those loads across neighboring instances.
+ //
+ // Compute shaders commonly work with unnormalized texture coordinates
+ // (where coordinates are integers [0..W) and [0..H)), whereas the rest
+ // of Movit, including any inputs you may want to sample from, works
+ // with normalized coordinates ([0..1)). Movit gives you uniforms
+ // PREFIX(inv_output_size) and PREFIX(output_texcoord_adjust) that you
+ // can use to transform unnormalized to normalized, as well as a macro
+ // NORMALIZE_TEXTURE_COORDS(vec2) that does it for you.
+ //
+ // Since compute shaders have flexible output, it is difficult to chain other
+ // effects after them in the same phase, and thus, they will always be last.
+ // (This limitation may be lifted for the special case of one-to-one effects
+ // in the future.) Furthermore, they cannot write to the framebuffer, just to
+ // textures, so Movit may have to insert an extra phase just to do the output
+ // from a texture to the screen in some cases. However, this is transparent
+ // to both the effect and the user.
+ virtual bool is_compute_shader() const { return false; }
+
+ // For a compute shader (see the previous member function), what dimensions
+ // it should be invoked over. Called every frame, before uniforms are set
+ // (so you are allowed to update uniforms based from this call).
+ virtual void get_compute_dimensions(unsigned output_width, unsigned output_height,
+ unsigned *x, unsigned *y, unsigned *z) const {
+ *x = output_width;
+ *y = output_height;
+ *z = 1;
+ }
+
// Tells the effect the resolution of each of its input.
// This will be called every frame, and always before get_output_size(),
// so you can change your output size based on the input if so desired.
//
// Neither of these take ownership of the pointer.
- // int is special since GLSL pre-1.30 doesn't have integer uniforms.
- // Thus, ints that you register will _not_ be converted to GLSL uniforms.
+ // These correspond directly to int/float/vec2/vec3/vec4 in GLSL.
void register_int(const std::string &key, int *value);
-
- // These correspond directly to float/vec2/vec3/vec4 in GLSL.
void register_float(const std::string &key, float *value);
void register_vec2(const std::string &key, float *values);
void register_vec3(const std::string &key, float *values);
void register_uniform_vec2(const std::string &key, const float *values);
void register_uniform_vec3(const std::string &key, const float *values);
void register_uniform_vec4(const std::string &key, const float *values);
+ void register_uniform_float_array(const std::string &key, const float *values, size_t num_values);
void register_uniform_vec2_array(const std::string &key, const float *values, size_t num_values);
+ void register_uniform_vec3_array(const std::string &key, const float *values, size_t num_values);
void register_uniform_vec4_array(const std::string &key, const float *values, size_t num_values);
void register_uniform_mat3(const std::string &key, const Eigen::Matrix3d *matrix);
std::map<std::string, float *> params_vec4;
// Picked out by EffectChain during finalization.
- 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<float> > uniforms_vec2_array;
- std::vector<Uniform<float> > uniforms_vec4_array;
- 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<float>> uniforms_float_array;
+ std::vector<Uniform<float>> uniforms_vec2_array;
+ std::vector<Uniform<float>> uniforms_vec3_array;
+ std::vector<Uniform<float>> uniforms_vec4_array;
+ std::vector<Uniform<Eigen::Matrix3d>> uniforms_mat3;
friend class EffectChain;
};