tunnel-runner

commit ad82cc27cecaaf85c18b19deac03e09530bd2f80
Author: amin <dev@aminmesbah.com>
Date:   Sat, 12 Nov 2016 06:16:28 +0000

Create empty sdl buffer.

FossilOrigin-Name: 05dba8bdbc073003db14c7dbfd733641c090d53926468230756fc5081d474bb2
Diffstat:
A
.gitignore
 | 
1
+
A
Makefile
 | 
7
+++++++
A
sdl_tunnel_flyer.cpp
 | 
197
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

3 files changed, 205 insertions(+), 0 deletions(-)
diff --git a/.gitignore b/.gitignore
@@ -0,0 +1 @@
+tunnel-flyer
diff --git a/Makefile b/Makefile
@@ -0,0 +1,7 @@
+build:
+	g++ -std=c++11 -Wall -Wextra -g sdl_tunnel_flyer.cpp -o tunnel-flyer `sdl2-config --cflags --libs`
+
+run:
+	./tunnel-flyer
+
+test: build run
diff --git a/sdl_tunnel_flyer.cpp b/sdl_tunnel_flyer.cpp
@@ -0,0 +1,197 @@
+#include <SDL.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <sys/mman.h>
+
+#ifndef MAP_ANONYMOUS
+#define MAP_ANONYMOUS MAP_ANON
+#endif
+
+#define internal static
+#define local_persist static
+#define global_variable static
+
+typedef int8_t int8;
+typedef int16_t int16;
+typedef int32_t int32;
+typedef int64_t int64;
+
+typedef uint8_t uint8;
+typedef uint16_t uint16;
+typedef uint32_t uint32;
+typedef uint64_t uint64;
+
+#define BYTES_PER_PIXEL 4
+
+
+struct SDLOffscreenBuffer
+{
+    // NOTE(amin): pixels are always 32-bits wide. Memory order: BB GG RR XX.
+    SDL_Texture *texture;
+    void *memory;
+    int width;
+    int height;
+    int pitch;
+};
+
+
+struct SDLWindowDimension
+{
+    int width;
+    int height;
+};
+
+
+global_variable SDLOffscreenBuffer global_back_buffer;
+
+
+SDLWindowDimension
+sdl_get_window_dimension(SDL_Window *window)
+{
+    SDLWindowDimension result;
+    SDL_GetWindowSize(window, &result.width, &result.height);
+    return(result);
+}
+
+
+internal void
+sdl_resize_texture(SDLOffscreenBuffer *buffer, SDL_Renderer *renderer, int width, int height)
+{
+    if (buffer->memory)
+    {
+        munmap(buffer->memory, buffer->width * buffer->height * BYTES_PER_PIXEL);
+    }
+
+    if (buffer->texture)
+    {
+        SDL_DestroyTexture(buffer->texture);
+    }
+
+    buffer->texture = SDL_CreateTexture(
+            renderer,
+            SDL_PIXELFORMAT_ARGB8888,
+            SDL_TEXTUREACCESS_STREAMING,
+            width, height);
+
+    buffer->width = width;
+    buffer->height = height;
+    buffer->pitch = width * BYTES_PER_PIXEL;
+
+    buffer->memory = mmap(
+            0,
+            width * height * BYTES_PER_PIXEL,
+            PROT_READ | PROT_WRITE,
+            MAP_PRIVATE | MAP_ANONYMOUS,
+            -1, 0);
+}
+
+
+internal void
+sdl_update_window(SDL_Window *window, SDL_Renderer *renderer, SDLOffscreenBuffer buffer)
+{
+    if (SDL_UpdateTexture(buffer.texture, 0, buffer.memory, buffer.pitch))
+    {
+        // TODO(amin): Handle this error
+    }
+
+    SDL_RenderCopy(renderer, buffer.texture, 0, 0);
+    SDL_RenderPresent(renderer);
+}
+
+
+bool
+handle_event(SDL_Event *event)
+{
+    bool should_quit = false;
+
+    switch(event->type)
+    {
+        case SDL_QUIT:
+        {
+            printf("SDL_QUIT\n");
+            should_quit = true;
+        } break;
+
+        case SDL_WINDOWEVENT:
+        {
+            switch(event->window.event)
+            {
+                case SDL_WINDOWEVENT_SIZE_CHANGED:
+                {
+                    SDL_Window *window = SDL_GetWindowFromID(event->window.windowID);
+                    SDL_Renderer *renderer = SDL_GetRenderer(window);
+                    printf("SDL_WINDOWEVENT_SIZE_CHANGED (%d, %d)\n", event->window.data1, event->window.data2);
+                    sdl_resize_texture(&global_back_buffer, renderer, event->window.data1, event->window.data2);
+                } break;
+
+                case SDL_WINDOWEVENT_FOCUS_GAINED:
+                {
+                    printf("SDL_WINDOWEVENT_FOCUS_GAINED\n");
+                } break;
+
+                case SDL_WINDOWEVENT_EXPOSED:
+                {
+                    SDL_Window *window = SDL_GetWindowFromID(event->window.windowID);
+                    SDL_Renderer *renderer = SDL_GetRenderer(window);
+                    sdl_update_window(window, renderer, global_back_buffer);
+                } break;
+            }
+        } break;
+    }
+    return(should_quit);
+}
+
+
+int main(void)
+{
+    if (SDL_Init(SDL_INIT_VIDEO) != 0)
+    {
+        // TODO(amin): log SDL_Init error
+    }
+
+    SDL_Window *window = SDL_CreateWindow(
+            "Tunnel Flyer",
+            SDL_WINDOWPOS_UNDEFINED,
+            SDL_WINDOWPOS_UNDEFINED,
+            640,
+            480,
+            SDL_WINDOW_RESIZABLE);
+
+    if (window)
+    {
+        SDL_Renderer *renderer = SDL_CreateRenderer(window, -1, 0);
+
+        if (renderer)
+        {
+            bool running = true;
+            SDLWindowDimension dimension = sdl_get_window_dimension(window);
+            sdl_resize_texture(&global_back_buffer, renderer, dimension.width, dimension.height);
+
+            while (running)
+            {
+                SDL_Event event;
+
+                while (SDL_PollEvent(&event))
+                {
+                    if (handle_event(&event))
+                    {
+                        running = false;
+                    }
+                }
+
+                sdl_update_window(window, renderer, global_back_buffer);
+            }
+        }
+        else
+        {
+            // TODO(amin): log SDL_Renderer error
+        }
+    }
+    else
+    {
+        // TODO(amin): log SDL_Window error
+    }
+
+    SDL_Quit();
+    return(0);
+}