Remove some unneeded conversions from ResampleEffect. Speeds up texture generation...

[movit] / effect_chain.h

diff --git a/effect_chain.h b/effect_chain.h
index ea4926b304efafad329e7309caf34d9252058544..6a6539955c4adf43bb4938cde62c70e39c9b19b0 100644 (file)
--- a/effect_chain.h
+++ b/effect_chain.h
@@ -259,23 +259,46 @@ public:
        }
        Effect *add_effect(Effect *effect, const std::vector<Effect *> &inputs);
 
-       // Adds an RGBA output. Note that you can have at most one RGBA output and one
-       // Y'CbCr output (see below for details).
+       // Adds an RGBA output. Note that you can have at most one RGBA output and two
+       // Y'CbCr outputs (see below for details).
        void add_output(const ImageFormat &format, OutputAlphaFormat alpha_format);
 
-       // Adds an YCbCr output. Note that you can only have one output.
-       // Currently, only chunked packed output is supported, and only 4:4:4
-       // (so chroma_subsampling_x and chroma_subsampling_y must both be 1).
+       // Adds an YCbCr output. Note that you can only have at most two Y'CbCr
+       // outputs, and they must have the same <ycbcr_format> and <type>.
+       // (This limitation may be lifted in the future, to allow e.g. simultaneous
+       // 8- and 10-bit output. Currently, multiple Y'CbCr outputs are only
+       // useful in some very limited circumstances, like if one texture goes
+       // to some place you cannot easily read from later.)
        //
-       // If you have both RGBA and Y'CbCr output, the RGBA output will come
+       // Only 4:4:4 output is supported due to fragment shader limitations,
+       // so chroma_subsampling_x and chroma_subsampling_y must both be 1.
+       // <type> should match the data type of the FBO you are rendering to,
+       // so that if you use 16-bit output (GL_UNSIGNED_SHORT), you will get
+       // 8-, 10- or 12-bit output correctly as determined by <ycbcr_format.num_levels>.
+       // Using e.g. ycbcr_format.num_levels == 1024 with GL_UNSIGNED_BYTE is
+       // nonsensical and invokes undefined behavior.
+       //
+       // If you have both RGBA and Y'CbCr output(s), the RGBA output will come
        // in the last draw buffer. Also, <format> and <alpha_format> must be
        // identical between the two.
        void add_ycbcr_output(const ImageFormat &format, OutputAlphaFormat alpha_format,
                              const YCbCrFormat &ycbcr_format,
-                             YCbCrOutputSplitting output_splitting = YCBCR_OUTPUT_INTERLEAVED);
+                             YCbCrOutputSplitting output_splitting = YCBCR_OUTPUT_INTERLEAVED,
+                             GLenum output_type = GL_UNSIGNED_BYTE);
+
+       // Change Y'CbCr output format. (This can be done also after finalize()).
+       // Note that you are not allowed to change subsampling parameters;
+       // however, you can change the color space parameters, ie.,
+       // luma_coefficients, full_range and num_levels.
+       void change_ycbcr_output_format(const YCbCrFormat &ycbcr_format);
 
        // Set number of output bits, to scale the dither.
        // 8 is the right value for most outputs.
+       //
+       // Special note for 10- and 12-bit Y'CbCr packed into GL_UNSIGNED_SHORT:
+       // This is relative to the actual output, not the logical one, so you should
+       // specify 16 here, not 10 or 12.
+       //
        // The default, 0, is a special value that means no dither.
        void set_dither_bits(unsigned num_bits)
        {
@@ -479,13 +502,16 @@ private:
        ImageFormat output_format;
        OutputAlphaFormat output_alpha_format;
 
-       bool output_color_rgba, output_color_ycbcr;
-       YCbCrFormat output_ycbcr_format;              // If output_color_ycbcr is true.
-       YCbCrOutputSplitting output_ycbcr_splitting;  // If output_color_ycbcr is true.
+       bool output_color_rgba;
+       int num_output_color_ycbcr;                      // Max 2.
+       YCbCrFormat output_ycbcr_format;                 // If num_output_color_ycbcr is > 0.
+       GLenum output_ycbcr_type;                        // If num_output_color_ycbcr is > 0.
+       YCbCrOutputSplitting output_ycbcr_splitting[2];  // If num_output_color_ycbcr is > N.
 
        std::vector<Node *> nodes;
        std::map<Effect *, Node *> node_map;
        Effect *dither_effect;
+       Node *ycbcr_conversion_effect_node;
 
        std::vector<Input *> inputs;  // Also contained in nodes.
        std::vector<Phase *> phases;