poc

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "vendor/rpi-rgb-led-matrix"]
+	path = vendor/rpi-rgb-led-matrix
+	url = https://github.com/hzeller/rpi-rgb-led-matrix.git

matrix.go

@@ -0,0 +1,112 @@
+package main
+
+/*
+#cgo CFLAGS: -std=c99 -Ivendor/rpi-rgb-led-matrix/include -DSHOW_REFRESH_RATE
+#cgo LDFLAGS: -lrgbmatrix -Lvendor/rpi-rgb-led-matrix/lib -lstdc++ -lm
+#include <led-matrix-c.h>
+#include <string.h>
+#include <stdio.h>
+#include <unistd.h>
+
+struct RGBLedMatrix *matrix;
+struct LedCanvas *offscreen_canvas;
+
+void setCanvas(struct LedCanvas *offscreen_canvas, const uint32_t pixels[]) {
+  int i, x, y;
+	uint32_t color;
+		for (y = 0; y < 32; ++y) {
+			for (x = 0; x < 64; ++x) {
+				i = x + (y * 64);
+
+    		color = pixels[i];
+    		led_canvas_set_pixel(offscreen_canvas, x, y,
+					(color >> 16) & 255, (color >> 8) & 255, color & 255);
+			}
+	}
+}
+
+int example(struct RGBLedMatrixOptions *options) {
+  struct LedCanvas *offscreen_canvas;
+  int width, height;
+  int x, y, i;
+
+  matrix = led_matrix_create_from_options(options, NULL, NULL);
+  if (matrix == NULL)
+    return 1;
+
+  offscreen_canvas = led_matrix_create_offscreen_canvas(matrix);
+
+  led_canvas_get_size(offscreen_canvas, &width, &height);
+
+  fprintf(stderr, "Size: %dx%d. Hardware gpio mapping: %s\n",
+          width, height, options->hardware_mapping);
+
+  for (i = 0; i < 1000; ++i) {
+    for (y = 0; y < height; ++y) {
+      for (x = 0; x < width; ++x) {
+        led_canvas_set_pixel(offscreen_canvas, x, y, i & 0xff, x, y);
+      }
+    }
+
+    offscreen_canvas = led_matrix_swap_on_vsync(matrix, offscreen_canvas);
+  }
+
+  led_matrix_delete(matrix);
+
+  return 0;
+}
+*/
+import "C"
+import (
+	"fmt"
+	"image/color"
+	"time"
+	"unsafe"
+)
+
+func main() {
+	o := &C.struct_RGBLedMatrixOptions{}
+	o.rows = 32
+	o.chain_length = 2
+
+	s := time.Now()
+	C.example(o)
+	fmt.Println(time.Since(s))
+
+	s = time.Now()
+	example(o)
+	fmt.Println(time.Since(s))
+
+}
+
+func example(o *C.struct_RGBLedMatrixOptions) {
+	matrix := C.led_matrix_create_from_options(o, nil, nil)
+	if matrix == nil {
+		panic("jodido")
+	}
+
+	//offscreen := C.led_matrix_create_offscreen_canvas(matrix)
+	for i := 1; i < 1000; i++ {
+		p := make([]C.uint32_t, 2048)
+		for y := 0; y < 32; y++ {
+			for x := 0; x < 64; x++ {
+				pos := x + (y * 64)
+
+				c := color.RGBA{uint8(i & 0xff), uint8(x), uint8(y), 0}
+				p[pos] = C.uint32_t(colorToUint32(c))
+			}
+		}
+
+		C.setCanvas(matrix, (*C.uint32_t)(unsafe.Pointer(&p[0])))
+		//offscreen = C.led_matrix_swap_on_vsync(matrix, offscreen)
+	}
+
+	C.led_matrix_delete(matrix)
+}
+
+func colorToUint32(c color.Color) uint32 {
+	// A color's RGBA method returns values in the range [0, 65535]
+	red, green, blue, _ := c.RGBA()
+	//	r<<16 | g<<8 | b
+	return (red>>8)<<16 | (green>>8)<<8 | blue>>8
+}

vendor/rpi-rgb-led-matrix

@@ -0,0 +1 @@
+Subproject commit 24ecf1d8393d55880b013e068a7d3575c13ab8ac