Convert xor_gen example into gym application

Author: rexim

Diff for: .gitignore

@@ -1,4 +1,4 @@
-xor_gen
+xor
 adder_gen
 gym
 img2nn

Diff for: build.sh

@@ -6,6 +6,6 @@ CFLAGS="-O3 -Wall -Wextra -I./thirdparty/"
 LIBS="-lm"
 
 clang $CFLAGS -o adder_gen adder_gen.c $LIBS
-clang $CFLAGS -o xor_gen xor_gen.c $LIBS
+clang $CFLAGS `pkg-config --cflags raylib` -o xor xor.c $LIBS `pkg-config --libs raylib` -lglfw -ldl -lpthread
 clang $CFLAGS `pkg-config --cflags raylib` -o gym gym.c $LIBS `pkg-config --libs raylib` -lglfw -ldl -lpthread
 clang $CFLAGS `pkg-config --cflags raylib` -o img2nn img2nn.c $LIBS `pkg-config --libs raylib` -lglfw -ldl -lpthread

Diff for: fonts/iosevka-regular.ttf

@@ -66,6 +66,7 @@ void nn_backprop(NN nn, NN g, Mat ti, Mat to);
 void nn_learn(NN nn, NN g, float rate);
 
 #ifdef NN_ENABLE_GYM
+#include <float.h>
 #include "raylib.h"
 
 typedef struct {

Diff for: nn.h

@@ -0,0 +1,116 @@
+#define NN_IMPLEMENTATION
+#define NN_ENABLE_GYM
+#include "nn.h"
+
+size_t arch[] = {2, 2, 1};
+size_t max_epoch = 100*1000;
+size_t epochs_per_frame = 103;
+float rate = 1.0f;
+bool paused = true;
+
+void verify_nn_gate(Font font, NN nn, float rx, float ry, float rw, float rh)
+{
+    (void) rw;
+    char buffer[256];
+    float s = rh*0.06;
+    float pad = rh*0.03;
+    for (size_t i = 0; i < 2; ++i) {
+        for (size_t j = 0; j < 2; ++j) {
+            MAT_AT(NN_INPUT(nn), 0, 0) = i;
+            MAT_AT(NN_INPUT(nn), 0, 1) = j;
+            nn_forward(nn);
+            snprintf(buffer, sizeof(buffer), "%zu @ %zu == %f", i, j, MAT_AT(NN_OUTPUT(nn), 0, 0));
+            DrawTextEx(font, buffer, CLITERAL(Vector2){rx, ry + (i*2 + j)*(s + pad)}, s, 0, WHITE);
+        }
+    }
+}
+
+int main(void)
+{
+    Mat t = mat_alloc(4, 3);
+    for (size_t i = 0; i < 2; ++i) {
+        for (size_t j = 0; j < 2; ++j) {
+            size_t row = i*2 + j;
+            MAT_AT(t, row, 0) = i;
+            MAT_AT(t, row, 1) = j;
+            MAT_AT(t, row, 2) = i^j;
+        }
+    }
+
+    Mat ti = {
+        .rows = t.rows,
+        .cols = 2,
+        .stride = t.stride,
+        .es = &MAT_AT(t, 0, 0),
+    };
+
+    Mat to = {
+        .rows = t.rows,
+        .cols = 1,
+        .stride = t.stride,
+        .es = &MAT_AT(t, 0, ti.cols),
+    };
+
+
+    NN nn = nn_alloc(arch, ARRAY_LEN(arch));
+    NN g = nn_alloc(arch, ARRAY_LEN(arch));
+    nn_rand(nn, -1, 1);
+
+    size_t WINDOW_FACTOR = 80;
+    size_t WINDOW_WIDTH = (16*WINDOW_FACTOR);
+    size_t WINDOW_HEIGHT = (9*WINDOW_FACTOR);
+
+    SetConfigFlags(FLAG_WINDOW_RESIZABLE);
+    InitWindow(WINDOW_WIDTH, WINDOW_HEIGHT, "xor");
+    SetTargetFPS(60);
+
+    Font font = LoadFontEx("./fonts/iosevka-regular.ttf", 72, NULL, 0);
+    SetTextureFilter(font.texture, TEXTURE_FILTER_BILINEAR);
+
+    Plot plot = {0};
+
+    size_t epoch = 0;
+    while (!WindowShouldClose()) {
+        if (IsKeyPressed(KEY_SPACE)) {
+            paused = !paused;
+        }
+        if (IsKeyPressed(KEY_R)) {
+            epoch = 0;
+            nn_rand(nn, -1, 1);
+            plot.count = 0;
+        }
+
+        for (size_t i = 0; i < epochs_per_frame && !paused && epoch < max_epoch; ++i) {
+            nn_backprop(nn, g, ti, to);
+            nn_learn(nn, g, rate);
+            epoch += 1;
+            da_append(&plot, nn_cost(nn, ti, to));
+        }
+
+        BeginDrawing();
+        Color background_color = {0x18, 0x18, 0x18, 0xFF};
+        ClearBackground(background_color);
+        {
+            int w = GetRenderWidth();
+            int h = GetRenderHeight();
+
+            int rw = w/3;
+            int rh = h*2/3;
+            int rx = 0;
+            int ry = h/2 - rh/2;
+
+            gym_plot(plot, rx, ry, rw, rh);
+            rx += rw;
+            gym_render_nn(nn, rx, ry, rw, rh);
+            rx += rw;
+            verify_nn_gate(font, nn, rx, ry, rw, rh);
+
+            char buffer[256];
+            snprintf(buffer, sizeof(buffer), "Epoch: %zu/%zu, Rate: %f, Cost: %f", epoch, max_epoch, rate, nn_cost(nn, ti, to));
+            DrawTextEx(font, buffer, CLITERAL(Vector2){}, h*0.04, 0, WHITE);
+        }
+        EndDrawing();
+    }
+
+    return 0;
+}