From eccd5c03c35127b10dc85e51e671f4d0305efd86 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Mon, 10 Nov 2025 13:33:50 -0800
Subject: [PATCH] testautomation: added tests to cover linear <-> sRGB
colorspace conversion
---
test/testautomation_render.c | 207 +++++++++++++++++++++++++++++++++++
1 file changed, 207 insertions(+)
diff --git a/test/testautomation_render.c b/test/testautomation_render.c
index 2ea88c7d4548e..b6eeb35aad546 100644
--- a/test/testautomation_render.c
+++ b/test/testautomation_render.c
@@ -2102,6 +2102,203 @@ static int SDLCALL render_testTextureState(void *arg)
return TEST_COMPLETED;
}
+static void CheckUniformColor(float expected)
+{
+ SDL_Surface *surface = SDL_RenderReadPixels(renderer, NULL);
+ if (surface) {
+ const float epsilon = 0.0001f;
+ float r, g, b, a;
+ CHECK_FUNC(SDL_ReadSurfacePixelFloat, (surface, 0, 0, &r, &g, &b, &a));
+ SDLTest_AssertCheck(
+ SDL_fabs(r - expected) <= epsilon &&
+ SDL_fabs(g - expected) <= epsilon &&
+ SDL_fabs(b - expected) <= epsilon &&
+ a == 1.0f,
+ "Check color, expected %g,%g,%g,%g, got %g,%g,%g,%g",
+ expected, expected, expected, 1.0f, r, g, b, a);
+ SDL_DestroySurface(surface);
+ } else {
+ SDLTest_AssertCheck(surface != NULL, "Validate result from SDL_RenderReadPixels, got NULL, %s", SDL_GetError());
+ }
+}
+
+/**
+ * Tests colorspace support (sRGB -> linear)
+ */
+static int SDLCALL render_testColorspaceLinear(void *arg)
+{
+ SDL_PropertiesID props;
+ SDL_Texture *texture;
+ Uint32 pixel = 0xFF404040;
+
+ SDL_DestroyRenderer(renderer);
+
+ props = SDL_CreateProperties();
+ SDL_SetPointerProperty(props, SDL_PROP_RENDERER_CREATE_WINDOW_POINTER, window);
+ SDL_SetNumberProperty(props, SDL_PROP_RENDERER_CREATE_OUTPUT_COLORSPACE_NUMBER, SDL_COLORSPACE_SRGB_LINEAR);
+ renderer = SDL_CreateRendererWithProperties(props);
+ SDL_DestroyProperties(props);
+ if (!renderer) {
+ SDLTest_Log("Skipping test render_testColorspaceLinear, couldn't create a linear colorspace renderer");
+ return TEST_SKIPPED;
+ }
+
+ /* Verify conversion between sRGB and linear colorspaces */
+ texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_ARGB8888, SDL_TEXTUREACCESS_STATIC, 1, 1);
+ SDLTest_AssertPass("Create texture");
+ SDLTest_AssertCheck(texture != NULL, "Check SDL_CreateTexture result");
+ CHECK_FUNC(SDL_UpdateTexture, (texture, NULL, &pixel, sizeof(pixel)));
+
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0, 0, 0, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+ CheckUniformColor(0.0f);
+
+ SDLTest_AssertPass("Checking sRGB clear 0x40");
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0x40, 0x40, 0x40, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+ CheckUniformColor(0.0512695f);
+
+ /* Clear target to 0 */
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0, 0, 0, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+
+ SDLTest_AssertPass("Checking sRGB draw 0x40");
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0x40, 0x40, 0x40, 255));
+ CHECK_FUNC(SDL_RenderPoint, (renderer, 0.0f, 0.0f));
+ CheckUniformColor(0.0512695f);
+
+ /* Clear target to 0 */
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0, 0, 0, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+
+ SDLTest_AssertPass("Checking sRGB texture 0x40");
+ CHECK_FUNC(SDL_RenderTexture, (renderer, texture, NULL, NULL));
+ CheckUniformColor(0.0512695f);
+
+ /* Clear target to 0 */
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0, 0, 0, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+
+ SDL_SetRenderColorScale(renderer, 2.0f);
+
+ SDLTest_AssertPass("Checking sRGB clear 0x40 with color scale 2.0");
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0x40, 0x40, 0x40, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+ CheckUniformColor(0.102478f);
+
+ /* Clear target to 0 */
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0, 0, 0, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+
+ SDLTest_AssertPass("Checking sRGB draw 0x40 with color scale 2.0f");
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0x40, 0x40, 0x40, 255));
+ CHECK_FUNC(SDL_RenderPoint, (renderer, 0.0f, 0.0f));
+ CheckUniformColor(0.102478f);
+
+ /* Clear target to 0 */
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0, 0, 0, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+
+ SDLTest_AssertPass("Checking sRGB texture 0x40 with color scale 2.0f");
+ CHECK_FUNC(SDL_RenderTexture, (renderer, texture, NULL, NULL));
+ CheckUniformColor(0.102478f);
+
+ SDL_DestroyTexture(texture);
+
+ return TEST_COMPLETED;
+}
+
+/**
+ * Tests colorspace support (linear -> sRGB)
+ */
+static int SDLCALL render_testColorspaceSRGB(void *arg)
+{
+ bool supports_float_textures;
+ const SDL_PixelFormat *texture_formats;
+ int i;
+ SDL_Texture *texture;
+ float pixel[4] = { 0.25f, 0.25f, 0.25f, 1.0f };
+
+ supports_float_textures = false;
+ texture_formats = (const SDL_PixelFormat *)SDL_GetPointerProperty(SDL_GetRendererProperties(renderer), SDL_PROP_RENDERER_TEXTURE_FORMATS_POINTER, NULL);
+ if (texture_formats) {
+ for (i = 0; texture_formats[i] != SDL_PIXELFORMAT_UNKNOWN; ++i) {
+ if (SDL_ISPIXELFORMAT_FLOAT(texture_formats[i])) {
+ supports_float_textures = true;
+ break;
+ }
+ }
+ }
+ if (!supports_float_textures) {
+ SDLTest_Log("Skipping test render_testColorspaceSRGB, renderer doesn't support float textures");
+ return TEST_SKIPPED;
+ }
+
+ /* Verify conversion between sRGB and linear colorspaces */
+ texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_RGBA128_FLOAT, SDL_TEXTUREACCESS_STATIC, 1, 1);
+ SDLTest_AssertPass("Create texture");
+ SDLTest_AssertCheck(texture != NULL, "Check SDL_CreateTexture result");
+ CHECK_FUNC(SDL_UpdateTexture, (texture, NULL, &pixel, sizeof(pixel)));
+
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0, 0, 0, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+ CheckUniformColor(0.0f);
+
+ SDLTest_AssertPass("Checking sRGB clear 0x40");
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0x40, 0x40, 0x40, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+ CheckUniformColor(0.25098f);
+
+ /* Clear target to 0 */
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0, 0, 0, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+
+ SDLTest_AssertPass("Checking sRGB draw 0x40");
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0x40, 0x40, 0x40, 255));
+ CHECK_FUNC(SDL_RenderPoint, (renderer, 0.0f, 0.0f));
+ CheckUniformColor(0.25098f);
+
+ /* Clear target to 0 */
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0, 0, 0, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+
+ SDLTest_AssertPass("Checking linear texture 0.25");
+ CHECK_FUNC(SDL_RenderTexture, (renderer, texture, NULL, NULL));
+ CheckUniformColor(0.537255f);
+
+ /* Clear target to 0 */
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0, 0, 0, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+
+ SDL_SetRenderColorScale(renderer, 2.0f);
+
+ SDLTest_AssertPass("Checking sRGB clear 0x40 with color scale 2.0");
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0x40, 0x40, 0x40, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+ CheckUniformColor(0.501961f);
+
+ /* Clear target to 0 */
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0, 0, 0, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+
+ SDLTest_AssertPass("Checking sRGB draw 0x40 with color scale 2.0f");
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0x40, 0x40, 0x40, 255));
+ CHECK_FUNC(SDL_RenderPoint, (renderer, 0.0f, 0.0f));
+ CheckUniformColor(0.501961f);
+
+ /* Clear target to 0 */
+ CHECK_FUNC(SDL_SetRenderDrawColor, (renderer, 0, 0, 0, 255));
+ CHECK_FUNC(SDL_RenderClear, (renderer));
+
+ SDLTest_AssertPass("Checking linear texture 0.25 with color scale 2.0f");
+ CHECK_FUNC(SDL_RenderTexture, (renderer, texture, NULL, NULL));
+ CheckUniformColor(0.737255f);
+
+ SDL_DestroyTexture(texture);
+
+ return TEST_COMPLETED;
+}
+
/* ================= Test References ================== */
/* Render test cases */
@@ -2173,6 +2370,14 @@ static const SDLTest_TestCaseReference renderTestRGBSurfaceNoAlpha = {
render_testRGBSurfaceNoAlpha, "render_testRGBSurfaceNoAlpha", "Tests RGB surface with no alpha using software renderer", TEST_ENABLED
};
+static const SDLTest_TestCaseReference renderTestColorspaceLinear = {
+ render_testColorspaceLinear, "render_testColorspaceLinear", "Tests colorspace support (sRGB -> linear)", TEST_ENABLED
+};
+
+static const SDLTest_TestCaseReference renderTestColorspaceSRGB = {
+ render_testColorspaceSRGB, "render_testColorspaceSRGB", "Tests colorspace support (linear -> sRGB)", TEST_ENABLED
+};
+
/* Sequence of Render test cases */
static const SDLTest_TestCaseReference *renderTests[] = {
&renderTestGetNumRenderDrivers,
@@ -2192,6 +2397,8 @@ static const SDLTest_TestCaseReference *renderTests[] = {
&renderTestTextureState,
&renderTestGetSetTextureScaleMode,
&renderTestRGBSurfaceNoAlpha,
+ &renderTestColorspaceLinear,
+ &renderTestColorspaceSRGB,
NULL
};