1 files changed, 106 insertions, 0 deletions
diff --git a/libglitter_compose_double.c b/libglitter_compose_double.c
new file mode 100644
index 0000000..ba094f0
--- /dev/null
+++ b/libglitter_compose_double.c
@@ -0,0 +1,106 @@
+/* See LICENSE file for copyright and license details. */
+#include "libglitter.h"
+
+
+static void
+generic(double **outputs, size_t noutputs, const double *restrict input,
+        size_t output_rowsize, size_t output_cellsize, size_t input_rowsize,
+        size_t width, size_t height, size_t widthmul, size_t heightmul,
+        const uint8_t *restrict cellmap, const double *restrict ncellweights)
+{
+	size_t y, x, iy, ix, output_y, output_i, input_blanking;
+	uint8_t channel;
+	double value;
+
+	output_rowsize *= output_cellsize;
+	input_blanking = input_rowsize * heightmul - width * widthmul;
+
+	for (y = 0, output_y = 0; y < height; y++, output_y += output_rowsize) {
+		for (x = 0, output_i = output_y; x < width; x++, output_i += output_cellsize) {
+
+			for (iy = 0; iy < heightmul; iy++) {
+				for (ix = 0; ix < widthmul; ix++) {
+					channel = cellmap[iy * widthmul + ix];
+
+					value = input[iy * input_rowsize + ix];
+					value *= ncellweights[channel];
+
+					outputs[channel][output_i] += value;
+				}
+			}
+			input = &input[widthmul];
+		}
+		input = &input[input_blanking];
+	}
+}
+
+
+static void
+vstrips(double **outputs_, const double *restrict input, size_t output_rowsize, size_t output_cellsize,
+        size_t input_rowsize, size_t width, size_t height, const uint8_t *restrict cellmap)
+{
+	double *outputs[3];
+	size_t y, x, output_y, output_i, input_blanking;
+
+	outputs[0] = outputs_[cellmap[0]];
+	outputs[1] = outputs_[cellmap[1]];
+	outputs[2] = outputs_[cellmap[2]];
+
+	output_rowsize *= output_cellsize;
+	input_blanking = input_rowsize - width * 3;
+
+	for (y = 0, output_y = 0; y < height; y++, output_y += output_rowsize) {
+		for (x = 0, output_i = output_y; x < width; x++, output_i += output_cellsize) {
+
+			outputs[0][output_i] = input[0];
+			outputs[1][output_i] = input[1];
+			outputs[2][output_i] = input[2];
+			input = &input[3];
+		}
+		input = &input[input_blanking];
+	}
+}
+
+
+static void
+hstrips(double **outputs_, const double *restrict input, size_t output_rowsize, size_t output_cellsize,
+        size_t input_rowsize, size_t width, size_t height, const uint8_t *restrict cellmap)
+{
+	double *outputs[3];
+	size_t y, x, output_y, output_i, input_blanking;
+
+	outputs[0] = outputs_[cellmap[0]];
+	outputs[1] = outputs_[cellmap[1]];
+	outputs[2] = outputs_[cellmap[2]];
+
+	output_rowsize *= output_cellsize;
+	input_blanking = input_rowsize * 3 - width;
+
+	for (y = 0, output_y = 0; y < height; y++, output_y += output_rowsize) {
+		for (x = 0, output_i = output_y; x < width; x++, output_i += output_cellsize) {
+
+			outputs[0][output_i] = input[0 * input_rowsize];
+			outputs[1][output_i] = input[1 * input_rowsize];
+			outputs[2][output_i] = input[2 * input_rowsize];
+			input = &input[1];
+		}
+		input = &input[input_blanking];
+	}
+}
+
+
+void
+libglitter_compose_double(double **outputs, size_t noutputs, const double *restrict input,
+                          size_t output_rowsize, size_t output_cellsize, size_t input_rowsize,
+                          size_t width, size_t height, size_t widthmul, size_t heightmul,
+                          const uint8_t *restrict cellmap, const double *restrict ncellweights)
+{
+	if (noutputs == 3 && widthmul == 3 && heightmul == 1) {
+		vstrips(outputs, input, output_rowsize, output_cellsize, input_rowsize, width, height, cellmap);
+	} else if (noutputs == 3 && widthmul == 1 && heightmul == 3) {
+		hstrips(outputs, input, output_rowsize, output_cellsize, input_rowsize, width, height, cellmap);
+	} else {
+		generic(outputs, noutputs, input, output_rowsize, output_cellsize,
+		        input_rowsize, width, height, widthmul, heightmul, cellmap, ncellweights);
+	}
+}