#include <string>
#include <vector>
-#include <GL/gl.h>
+#include <assert.h>
+
+#include "opengl.h"
+
+class EffectChain;
// Can alias on a float[2].
struct Point2D {
void set_uniform_vec4_array(GLuint glsl_program_num, const std::string &prefix, const std::string &key, const float *values, size_t num_values);
class Effect {
-public:
+public:
+ // An identifier for this type of effect, mostly used for debug output
+ // (but some special names, like "ColorSpaceConversionEffect", holds special
+ // meaning). Same as the class name is fine.
+ virtual std::string effect_type_id() const = 0;
+
// Whether this effects expects its input (and output) to be in
// linear gamma, ie. without an applied gamma curve. Most effects
// will want this, although the ones that never actually look at
// set of RGB primaries; you would currently not get YCbCr
// or something similar).
//
- // Again, most effects will want this.
+ // Again, most effects will want this, but you can set it to false
+ // if you process each channel independently, equally _and_
+ // in a linear fashion.
virtual bool needs_srgb_primaries() const { return true; }
// Whether this effect expects its input to come directly from
// needs mipmaps, you will also get them).
virtual bool needs_mipmaps() const { return false; }
+ // Whether this effect wants to output to a different size than
+ // its input(s). If you set this to true, the output will be
+ // bounced to a texture (similarly to if the next effect set
+ // needs_texture_bounce()).
+ virtual bool changes_output_size() const { return false; }
+
+ // If changes_output_size() is true, you must implement this to tell
+ // the framework what output size you want.
+ //
+ // Note that it is explicitly allowed to change width and height
+ // from frame to frame; EffectChain will reallocate textures as needed.
+ virtual void get_output_size(unsigned *width, unsigned *height) const {
+ assert(false);
+ }
+
+ // How many inputs this effect will take (a fixed number).
+ // If you have only one input, it will be called INPUT() in GLSL;
+ // if you have several, they will be INPUT1(), INPUT2(), and so on.
+ virtual unsigned num_inputs() const { return 1; }
+
// Requests that this effect adds itself to the given effect chain.
// For most effects, the default will be fine, but for effects that
// consist of multiple passes, it is often useful to replace this
// with something that adds completely different things to the chain.
- virtual void add_self_to_effect_chain(std::vector<Effect *> *chain) {
- chain->push_back(this);
- }
+ virtual void add_self_to_effect_chain(EffectChain *graph, const std::vector<Effect *> &inputs);
// Outputs one GLSL uniform declaration for each registered parameter
// (see below), with the right prefix prepended to each uniform name.
// Returns the GLSL fragment shader string for this effect.
virtual std::string output_fragment_shader() = 0;
- // Set all uniforms the shader needs in the current GL context.
- // The default implementation sets one uniform per registered parameter.
+ // Set all OpenGL state that this effect needs before rendering.
+ // The default implementation sets one uniform per registered parameter,
+ // but no other state.
//
// <sampler_num> is the first free texture sampler. If you want to use
// textures, you can bind a texture to GL_TEXTURE0 + <sampler_num>,
// and then increment the number (so that the next effect in the chain
// will use a different sampler).
- //
- // NOTE: Currently this is also abused a bit to set other GL state
- // the effect might need.
- virtual void set_uniforms(GLuint glsl_program_num, const std::string& prefix, unsigned *sampler_num);
+ virtual void set_gl_state(GLuint glsl_program_num, const std::string& prefix, unsigned *sampler_num);
+
+ // If you set any special OpenGL state in set_gl_state(), you can clear it
+ // after rendering here. The default implementation does nothing.
+ virtual void clear_gl_state();
// Set a parameter; intended to be called from user code.
// Neither of these take ownership of the pointer.