rainbow

1 files changed, 25 insertions, 0 deletions

diff --git a/examples/rainbow.c b/examples/rainbow.c
new file mode 100644
index 0000000..33cbb2d
--- /dev/null
+++ b/examples/rainbow.c
@@ -0,0 +1,25 @@
+#include <stdio.h>
+#include <math.h>
+
+
+
+#include "../sponge.h"
+
+#define PI ((float)3.14159265358979323846)
+#define SPEED (2.0f / 360.0f * 2 * PI)
+static float angle = 0.0f;
+
+void draw_frame(sponge_Texture c) {
+    angle += SPEED;
+
+    float rf = (sinf(angle) + 1.0f) * 255.0f / 2.0f;
+    float gf = (sinf(angle + (PI * 2.0f / 3.0f)) + 1.0f) * 255.0f / 2.0f;
+    float bf = (sinf(angle + (PI * 4.0f / 3.0f)) + 1.0f) * 255.0f / 2.0f;
+
+    int r = (((int)rf) & 0xFF) << 16;
+    int g = (((int)gf) & 0xFF) << 8;
+    int b = (((int)bf) & 0xFF) << 0;
+
+    uint32_t color = 0xFF000000 | r | g | b;
+    sponge_clear(c, color);
+}