initial commit

2025-08-02 06:09:31 +03:00
commit 00015ffc03
85 changed files with 62051 additions and 0 deletions
--- a/FIRMWARE/humanshader.c
+++ b/FIRMWARE/humanshader.c
@@ -0,0 +1,113 @@
+// C version of humanshader
+// See https://humanshader.com/
+// (using a computer is clearly not as fun, but it is interesting to have
+//  a small not too computationally expensive raytracing program that
+//  can run on small softcores for PGAs).
+// Using the 16-bits version with no divide from here: https://www.shadertoy.com/view/XflXDs
+
+#define GL_width  71
+#define GL_height 40
+#include "GL_tty.h"
+
+void human_shader(
+    int x, int y, uint8_t* r_out, uint8_t* g_out, uint8_t* b_out
+) {
+    int R, B;
+
+    //-------------------------    
+    // Section A (2 MUL, 3 ADD)
+    //-------------------------    
+    int u = x-36;
+    int v = 18-y;
+    int u2 = u*u;
+    int v2 = v*v;
+    int h = u2 + v2;
+    //-------------------------  
+    
+    if( h < 200 ) 
+    {
+        //-------------------------------------
+        // Section B, Sphere (4/7 MUL, 5/9 ADD)
+        //-------------------------------------
+        R = 420;
+        B = 520;
+
+        int t = 5200 + (h<<3);
+        int p = (t*u)>>7;
+        int q = (t*v)>>7;
+        
+        // bounce light
+        int w = 18 + (((p*5-q*13))>>9);
+        if( w>0 ) R += w*w;
+        
+        // sky light / ambient occlusion
+        int o = q + 900;
+        R = (R*o)>>12;
+        B = (B*o)>>12;
+
+        // sun/key light
+        if( p > -q )
+        {
+            int w = (p+q)>>3;
+            R += w;
+            B += w;
+        }
+        //-------------------------  
+	}
+    else if( v<0 )
+    {
+        //-------------------------------------
+        // Section C, Ground (5/9 MUL, 6/9 ADD)
+        //-------------------------------------
+        R = 150 + (v<<1);
+        B = 50;
+        
+        int p = h + (v2<<3);
+        int c = 240*(-v) - p;
+
+        // sky light / ambient occlusion
+        if( c>1200 )
+        {
+            int o = (25*c)>>3;
+            o = (c*(7840-o)>>9) - 8560;
+            R = (R*o)>>10;
+            B = (B*o)>>10;
+        }
+
+        // sun/key light with soft shadow
+        int r = c + u*v;
+        int d = 3200 - h - (r<<1);
+        if( d>0 ) R += d;
+        //-------------------------  
+    }
+    else
+    {
+        //------------------------------
+        // Section D, Sky (1 MUL, 2 ADD)
+        //------------------------------
+        int c = x + (y<<2);
+        R = 132 + c;
+        B = 192 + c;
+        //-------------------------  
+    }
+    
+    //-------------------------
+    // Section E (3 MUL, 1 ADD)
+    //-------------------------
+    if(R > 255) R = 255;
+    if(B > 255) B = 255;
+    
+    int G = (R*11 + 5*B)>>4;
+    //-------------------------  
+    
+    *r_out = (uint8_t)R;
+    *g_out = (uint8_t)G;
+    *b_out = (uint8_t)B;
+}
+
+int main() {
+    GL_init();
+    GL_scan_RGB(GL_width, GL_height, human_shader);
+    GL_terminate();
+    return 0;
+}