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Merge 3ad0e24a07 into 7341f04a12

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Project_HSI 2026-06-05 06:53:37 +10:00 • committed by GitHub
commit 4f20ecdae1
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1 changed files with 28 additions and 7 deletions
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35
test/testsoftwaretransparent.c
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@ -15,6 +15,8 @@
#define SQUARE_SIZE 100.0f
static bool premult = false;
/* Draw opaque red squares at the four corners of the form, and draw a red square with an alpha value of 180 in the center of the form */
static void draw(SDL_Renderer *renderer)
{
@ -26,20 +28,24 @@ static void draw(SDL_Renderer *renderer)
SDL_SetRenderDrawColor(renderer, 0, 0, 0, 0);
SDL_RenderClear(renderer);
if (w >= 3 * SQUARE_SIZE && h >= 3 * SQUARE_SIZE) {
SDL_SetRenderDrawColor(renderer, 255, 0, 0, 255);
SDL_SetRenderDrawBlendMode(renderer, premult ? SDL_BLENDMODE_BLEND : SDL_BLENDMODE_NONE);
if (w >= 3 * SQUARE_SIZE && h >= 3 * SQUARE_SIZE) {
rect.x = 0.0f;
rect.y = 0.0f;
SDL_SetRenderDrawColor(renderer, 255, 0, 0, 255);
SDL_RenderFillRect(renderer, &rect);
rect.y = h - SQUARE_SIZE;
SDL_SetRenderDrawColor(renderer, 255, 0, 0, 170);
SDL_RenderFillRect(renderer, &rect);
rect.x = w - SQUARE_SIZE;
SDL_SetRenderDrawColor(renderer, 255, 0, 0, 85);
SDL_RenderFillRect(renderer, &rect);
rect.y = 0.0f;
SDL_SetRenderDrawColor(renderer, 255, 0, 0, 0);
SDL_RenderFillRect(renderer, &rect);
}
@ -47,6 +53,9 @@ static void draw(SDL_Renderer *renderer)
rect.x = (w - SQUARE_SIZE) / 2;
rect.y = (h - SQUARE_SIZE) / 2;
SDL_RenderFillRect(renderer, &rect);
SDL_SetRenderDrawColor(renderer, 0, 255, 255, 255);
SDL_RenderDebugText(renderer, 0, 0, premult ? "Premult'd" : "Straight");
}
int main(int argc, char *argv[])
@ -59,7 +68,7 @@ int main(int argc, char *argv[])
int return_code = 1;
state = SDLTest_CommonCreateState(argv, 0);
state = SDLTest_CommonCreateState(argv, SDL_INIT_VIDEO);
if (!state) {
return 1;
}
@ -81,11 +90,10 @@ int main(int argc, char *argv[])
goto quit;
}
/* Make sure we're setting the alpha channel while drawing */
SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_NONE);
/* We're ready to go! */
while (!done) {
bool renderNeeded = false;
while (SDL_PollEvent(&event)) {
switch (event.type) {
case SDL_EVENT_KEY_DOWN:
@ -95,7 +103,15 @@ int main(int argc, char *argv[])
break;
case SDL_EVENT_WINDOW_EXPOSED:
/* The software renderer is persistent, so only redraw as-needed */
draw(renderer);
renderNeeded = true;
break;
case SDL_EVENT_MOUSE_BUTTON_DOWN:
if (event.button.button == 1) {
// switch between premultiplied alpha and straight alpha
premult = !premult;
renderNeeded = true;
}
break;
case SDL_EVENT_QUIT:
done = true;
@ -105,6 +121,9 @@ int main(int argc, char *argv[])
}
}
if (renderNeeded)
draw(renderer);
/* Show everything on the screen and wait a bit */
SDL_RenderPresent(renderer);
SDL_Delay(100);
@ -120,3 +139,5 @@ quit:
SDLTest_CommonDestroyState(state);
return return_code;
}