SDL/test/testdrawchessboard.c
Sam Lantinga 7d94121606 You should call present when using a software renderer as well.
Fixes https://github.com/libsdl-org/SDL/issues/8676

(cherry picked from commit 581d1cab257a14cd235df2192f012abb0d4e36e0)
2023-12-11 08:44:11 -08:00

139 lines
3.7 KiB
C

/*
Copyright (C) 1997-2023 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely.
This file is created by : Nitin Jain (nitin.j4@samsung.com)
*/
/* Sample program: Draw a Chess Board by using SDL_CreateSoftwareRenderer API */
#include <stdlib.h>
#include <stdio.h>
#ifdef __EMSCRIPTEN__
#include <emscripten/emscripten.h>
#endif
#include "SDL.h"
SDL_Window *window;
SDL_Renderer *renderer;
SDL_Surface *surface;
int done;
void DrawChessBoard()
{
int row = 0, column = 0, x = 0;
SDL_Rect rect, darea;
/* Get the Size of drawing surface */
SDL_RenderGetViewport(renderer, &darea);
for (; row < 8; row++) {
column = row % 2;
x = column;
for (; column < 4 + (row % 2); column++) {
SDL_SetRenderDrawColor(renderer, 0, 0, 0, 0xFF);
rect.w = darea.w / 8;
rect.h = darea.h / 8;
rect.x = x * rect.w;
rect.y = row * rect.h;
x = x + 2;
SDL_RenderFillRect(renderer, &rect);
}
}
SDL_RenderPresent(renderer);
}
void loop()
{
SDL_Event e;
while (SDL_PollEvent(&e)) {
/* Re-create when window has been resized */
if ((e.type == SDL_WINDOWEVENT) && (e.window.event == SDL_WINDOWEVENT_SIZE_CHANGED)) {
SDL_DestroyRenderer(renderer);
surface = SDL_GetWindowSurface(window);
renderer = SDL_CreateSoftwareRenderer(surface);
/* Clear the rendering surface with the specified color */
SDL_SetRenderDrawColor(renderer, 0xFF, 0xFF, 0xFF, 0xFF);
SDL_RenderClear(renderer);
}
if (e.type == SDL_QUIT) {
done = 1;
#ifdef __EMSCRIPTEN__
emscripten_cancel_main_loop();
#endif
return;
}
if ((e.type == SDL_KEYDOWN) && (e.key.keysym.sym == SDLK_ESCAPE)) {
done = 1;
#ifdef __EMSCRIPTEN__
emscripten_cancel_main_loop();
#endif
return;
}
}
DrawChessBoard();
/* Got everything on rendering surface,
now Update the drawing image on window screen */
SDL_UpdateWindowSurface(window);
}
int main(int argc, char *argv[])
{
/* Enable standard application logging */
SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO);
/* Initialize SDL */
if (SDL_Init(SDL_INIT_VIDEO) != 0) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "SDL_Init fail : %s\n", SDL_GetError());
return 1;
}
/* Create window and renderer for given surface */
window = SDL_CreateWindow("Chess Board", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 640, 480, SDL_WINDOW_RESIZABLE);
if (!window) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Window creation fail : %s\n", SDL_GetError());
return 1;
}
surface = SDL_GetWindowSurface(window);
renderer = SDL_CreateSoftwareRenderer(surface);
if (!renderer) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Render creation for surface fail : %s\n", SDL_GetError());
return 1;
}
/* Clear the rendering surface with the specified color */
SDL_SetRenderDrawColor(renderer, 0xFF, 0xFF, 0xFF, 0xFF);
SDL_RenderClear(renderer);
/* Draw the Image on rendering surface */
done = 0;
#ifdef __EMSCRIPTEN__
emscripten_set_main_loop(loop, 0, 1);
#else
while (!done) {
loop();
}
#endif
SDL_Quit();
return 0;
}