diff options
| -rw-r--r-- | src/library_sdl.js | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/src/library_sdl.js b/src/library_sdl.js index 40fc5e7f..6a984c43 100644 --- a/src/library_sdl.js +++ b/src/library_sdl.js @@ -1,7 +1,7 @@ // To use emscripten's SDL library here, you need to define // Module.canvas and at least one of Module.ctx2D, Module.ctxGL. // -// More specifically, our SDL implementation will look for +// More specifically, for 2D our SDL implementation will look for // Module.canvas and Module.ctx2D. You should fill them using // something like // @@ -60,6 +60,25 @@ </html> */ +// Other stuff to take into account: +// +// * It's best to set the ctx stuff in your html file, as above. Otherwise you will need +// to edit the generated .js file each time you generate it. +// +// * Your code should not write a 32-bit value and expect that to set an RGBA pixel. +// The reason is that that data will be read as 8-bit values, and according to the +// load-store consistency assumption, it should be written that way (see docs/paper.pdf). +// Instead, do something like *ptr++ = R; *ptr++ = G; *ptr++ = B; +// +// * SQL_Quit will wipe the screen with random noise. This is intentional, in order +// to make it clear when SDL has shut down (which could be due to an error). If you +// want your output to remain on the screen, do not call SDL_Quit. +// +// * A normal C++ main loop with SDL_Delay will not work in JavaScript - there is no way +// to wait for a short time without locking up the web page entirely. The simplest +// solution here is to have a singleIteration() function which is a single loop +// iteration, and from JS to do something like setInterval(_singleIteration, 1/30) + mergeInto(Library, { $SDL__deps: ['$Browser'], $SDL: { |