Make pdf_functions public as fz_functions.

Implementations remain unexposed, but this means we can safely
pass functions in shades without having to 'sample' them (though
we may still choose to do this for speed).

2 files changed, 80 insertions, 0 deletions

diff --git a/fitz/fitz-internal.h b/fitz/fitz-internal.h
index 01f32172..a54a4780 100644
--- a/fitz/fitz-internal.h
+++ b/fitz/fitz-internal.h
@@ -1274,6 +1274,38 @@ fz_text *fz_clone_text(fz_context *ctx, fz_text *old);
 void fz_print_text(fz_context *ctx, FILE *out, fz_text*);
 
 /*
+ * The generic function support.
+ */
+
+typedef struct fz_function_s fz_function;
+
+void fz_eval_function(fz_context *ctx, fz_function *func, float *in, int inlen, float *out, int outlen);
+fz_function *fz_keep_function(fz_context *ctx, fz_function *func);
+void fz_drop_function(fz_context *ctx, fz_function *func);
+unsigned int fz_function_size(fz_function *func);
+#ifndef DEBUG
+void pdf_debug_function(fz_function *func);
+#endif
+
+enum
+{
+	FZ_FN_MAXN = FZ_MAX_COLORS,
+	FZ_FN_MAXM = FZ_MAX_COLORS
+};
+
+struct fz_function_s
+{
+	fz_storable storable;
+	unsigned int size;
+	int m;					/* number of input values */
+	int n;					/* number of output values */
+	void (*evaluate)(fz_context *ctx, fz_function *func, float *in, float *out);
+#ifndef NDEBUG
+	void (*debug)(fz_function *func);
+#endif
+};
+
+/*
  * The shading code uses gouraud shaded triangle meshes.
  */
 
diff --git a/fitz/res_func.c b/fitz/res_func.c
new file mode 100644
index 00000000..a8ffa907
--- /dev/null
+++ b/fitz/res_func.c
@@ -0,0 +1,48 @@
+#include "fitz-internal.h"
+
+void
+fz_eval_function(fz_context *ctx, fz_function *func, float *in_, int inlen, float *out_, int outlen)
+{
+	float fakein[FZ_FN_MAXM];
+	float fakeout[FZ_FN_MAXN];
+	float *in = in_;
+	float *out = out_;
+
+	if (inlen < func->m)
+	{
+		in = fakein;
+		memset(in, 0, sizeof(float) * func->m);
+		memcpy(in, in_, sizeof(float) * inlen);
+	}
+
+	if (outlen < func->n)
+	{
+		out = fakeout;
+		memset(out, 0, sizeof(float) * func->n);
+	}
+	else
+		memset(out, 0, sizeof(float) * outlen);
+
+	func->evaluate(ctx, func, in, out);
+
+	if (outlen < func->n)
+		memcpy(out_, out, sizeof(float) * outlen);
+}
+
+fz_function *
+fz_keep_function(fz_context *ctx, fz_function *func)
+{
+	return (fz_function *)fz_keep_storable(ctx, &func->storable);
+}
+
+void
+fz_drop_function(fz_context *ctx, fz_function *func)
+{
+	fz_drop_storable(ctx, &func->storable);
+}
+
+unsigned int
+fz_function_size(fz_function *func)
+{
+	return (func ? func->size : 0);
+}