Day 21 complete.

handmade.cpp

@@ -3,20 +3,22 @@
 
 #include <math.h>
 
-static void GameOutputSound(game_sound_output_buffer *SoundBuffer, S32 ToneHz)
+static void GameOutputSound(game_state *GameState, game_sound_output_buffer *SoundBuffer, S32 ToneHz)
 {
-    static F32 tSine;
     S16 ToneVolume = 8000;
     S32 WavePeriod = SoundBuffer->SamplesPerSecond / ToneHz;
 
     S16 *SampleOut = SoundBuffer->Samples;
     for(S32 SampleIndex = 0; SampleIndex < SoundBuffer->SampleCount; SampleIndex++) {
-        F32 SineValue = sinf(tSine);
+        F32 SineValue = sinf(GameState->tSine);
         S16 SampleValue = S16(SineValue * ToneVolume);
         *SampleOut++ = SampleValue;
         *SampleOut++ = SampleValue;
 
-        tSine += 2.0f * PI * 1.0f / (F32)WavePeriod;
+        GameState->tSine += 2.0f * (F32)PI * 1.0f / (F32)WavePeriod;
+        if(GameState->tSine > 2.0f*(F32)PI) {
+            GameState->tSine -= 2.0f*(F32)PI;
+        }
     }
 }
 
@@ -31,6 +33,7 @@ static void RenderWeirdGradient(game_offscreen_buffer *Buffer, S32 XOffset, S32
         for(S32 X = 0; X < Width; X++) {
             U8 Blue = (U8)(X + XOffset);
             U8 Green = (U8)(Y + YOffset);
+
             *Pixel = (Green << 8) | Blue;
             Pixel++;
         }
@@ -45,7 +48,7 @@ void UpdateAndRender(game_memory *Memory, game_input *Input, game_offscreen_buff
 
     game_state *GameState = (game_state *)Memory->PermanentStorage;
     if(!Memory->IsInitialized) {
-        char FileName[] = "/Users/igor/Developer/handmade_hero_course/handmade/code/sdl_handmade.cpp";
+        char FileName[] = "/home/igor/Developer/handmade/sdl_handmade.cpp";
         debug_read_file_result BitmapMemory = Memory->DEBUGPlatformReadEntireFile(FileName);
         if(BitmapMemory.Contents) {
             Memory->DEBUGPlatformWriteEntireFile("test.out", BitmapMemory.ContentsSize, BitmapMemory.Contents);
@@ -53,6 +56,7 @@ void UpdateAndRender(game_memory *Memory, game_input *Input, game_offscreen_buff
         }
 
         GameState->ToneHz = 256;
+        GameState->tSine = 0.0f;
 
         // TODO: Maybe more appropriate to do in the platform layer?
         Memory->IsInitialized = true;
@@ -83,6 +87,6 @@ void UpdateAndRender(game_memory *Memory, game_input *Input, game_offscreen_buff
         }
     }
 
-    GameOutputSound(SoundBuffer, GameState->ToneHz);
+    GameOutputSound(GameState, SoundBuffer, GameState->ToneHz);
     RenderWeirdGradient(Buffer, GameState->BlueOffset, GameState->GreenOffset);
 }

handmade.h

@@ -118,6 +118,8 @@ typedef struct game_state {
     S32 ToneHz;
     S32 GreenOffset;
     S32 BlueOffset;
+
+    F32 tSine;
 } game_state;
 
 #endif // HANDMADE_H

sdl_handmade.cpp

@@ -325,7 +325,7 @@ static F32 SDLGetSecondsElapsed(U64 Start, U64 End)
 }
 
 typedef struct sdl_game_code {
-    void *GameCode;
+    void *GameCodeDLL;
     void (*UpdateAndRender)(game_memory *, game_input *, game_offscreen_buffer *, game_sound_output_buffer *);
 
     B32 IsValid;
@@ -335,25 +335,35 @@ static sdl_game_code SDLLoadGameCode()
 {
     sdl_game_code Result = {0};
 
-    Result.GameCode = dlopen("./libhandmade.so", RTLD_NOW);
+    Result.GameCodeDLL = dlopen("./libhandmade.so", RTLD_NOW);
-    if(Result.GameCode) {
+    if(Result.GameCodeDLL) {
-        Result.UpdateAndRender = (void(*)(game_memory *, game_input *, game_offscreen_buffer *, game_sound_output_buffer *))dlsym(Result.GameCode, "UpdateAndRender");
+        Result.UpdateAndRender = (void(*)(game_memory *, game_input *, game_offscreen_buffer *, game_sound_output_buffer *))dlsym(Result.GameCodeDLL, "UpdateAndRender");
         if(!Result.UpdateAndRender) {
-            // TODO: Diagnostic.
+            // TODO: Diagnostic. dlerror()
-            fprintf(stderr, "%s\n", dlerror());
         }
+
+        Result.IsValid = Result.UpdateAndRender ? TRUE : FALSE;
     } else {
-        // TODO: Diagnostic.
+        // TODO: Diagnostic. dlerror()
-        fprintf(stderr, "%s\n", dlerror());
+    }
+
+    if(!Result.IsValid) {
+        Result.UpdateAndRender = NULL;
     }
 
     return Result;
 }
 
+static void SDLUnloadGameCode(sdl_game_code *GameCode)
+{
+    if(GameCode->GameCodeDLL)
+        dlclose(GameCode->GameCodeDLL); // NOTE: Might fail.
+    GameCode->IsValid = FALSE;
+    GameCode->UpdateAndRender = NULL;
+}
+
 S32 main(S32 argc, char *argv[])
 {
-    sdl_game_code Game = SDLLoadGameCode();
-
     if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_GAMECONTROLLER | SDL_INIT_AUDIO)) {
         /* TODO: This didn't work . . . */
     }
@@ -404,9 +414,9 @@ S32 main(S32 argc, char *argv[])
             GameMemory.PermanentStorage = mmap(BaseAddress, TotalStorageSize, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0);
             GameMemory.TransientStorage = (U8 *)(GameMemory.PermanentStorage) + GameMemory.PermanentStorageSize;
 
-            GameMemory.DEBUGPlatformReadEntireFile = DEBUGPlatformReadEntireFile;
+            GameMemory.DEBUGPlatformReadEntireFile = &DEBUGPlatformReadEntireFile;
-            GameMemory.DEBUGPlatformWriteEntireFile = DEBUGPlatformWriteEntireFile;
+            GameMemory.DEBUGPlatformWriteEntireFile = &DEBUGPlatformWriteEntireFile;
-            GameMemory.DEBUGPlatformFreeFileMemory = DEBUGPlatformFreeFileMemory;
+            GameMemory.DEBUGPlatformFreeFileMemory = &DEBUGPlatformFreeFileMemory;
 
             if(SoundOutput.Samples && GameMemory.PermanentStorage && GameMemory.TransientStorage) {
                 game_input Input[2];
@@ -421,6 +431,9 @@ S32 main(S32 argc, char *argv[])
                 U64 LastCycleCount;
 #endif
 
+                sdl_game_code Game = SDLLoadGameCode();
+                U32 LoadCounter = 0;
+
                 while(GlobalRunning) {
                     LastCounter = SDLGetWallClock();
 
@@ -432,6 +445,13 @@ S32 main(S32 argc, char *argv[])
                     S32 GameUpdateHz = MonitorRefreshHz / 2;
                     F32 TargetSecondsPerFrame = 1.0f / (F32)GameUpdateHz;
 
+                    if(LoadCounter > (U32)(GameUpdateHz * 2)) {
+                        SDLUnloadGameCode(&Game);
+                        Game = SDLLoadGameCode();
+                        LoadCounter = 0;
+                    }
+                    LoadCounter++;
+
                     game_controller_input *OldKeyboardController = GetController(OldInput, 0);
                     game_controller_input *NewKeyboardController = GetController(NewInput, 0);
                     game_controller_input ZeroController = {0};