SDL_test_compare.c
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/*
Simple DirectMedia Layer
Copyright (C) 1997-2016 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, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
/*
Based on automated SDL_Surface tests originally written by Edgar Simo 'bobbens'.
Rewritten for test lib by Andreas Schiffler.
*/
#include "SDL_config.h"
#include "SDL_test.h"
/* Counter for _CompareSurface calls; used for filename creation when comparisons fail */
static int _CompareSurfaceCount = 0;
/* Compare surfaces */
int SDLTest_CompareSurfaces(SDL_Surface *surface, SDL_Surface *referenceSurface, int allowable_error)
{
int ret;
int i,j;
int bpp, bpp_reference;
Uint8 *p, *p_reference;
int dist;
int sampleErrorX, sampleErrorY, sampleDist;
Uint8 R, G, B, A;
Uint8 Rd, Gd, Bd, Ad;
char imageFilename[128];
char referenceFilename[128];
/* Validate input surfaces */
if (surface == NULL || referenceSurface == NULL) {
return -1;
}
/* Make sure surface size is the same. */
if ((surface->w != referenceSurface->w) || (surface->h != referenceSurface->h)) {
return -2;
}
/* Sanitize input value */
if (allowable_error<0) {
allowable_error = 0;
}
SDL_LockSurface( surface );
SDL_LockSurface( referenceSurface );
ret = 0;
bpp = surface->format->BytesPerPixel;
bpp_reference = referenceSurface->format->BytesPerPixel;
/* Compare image - should be same format. */
for (j=0; j<surface->h; j++) {
for (i=0; i<surface->w; i++) {
p = (Uint8 *)surface->pixels + j * surface->pitch + i * bpp;
p_reference = (Uint8 *)referenceSurface->pixels + j * referenceSurface->pitch + i * bpp_reference;
SDL_GetRGBA(*(Uint32*)p, surface->format, &R, &G, &B, &A);
SDL_GetRGBA(*(Uint32*)p_reference, referenceSurface->format, &Rd, &Gd, &Bd, &Ad);
dist = 0;
dist += (R-Rd)*(R-Rd);
dist += (G-Gd)*(G-Gd);
dist += (B-Bd)*(B-Bd);
/* Allow some difference in blending accuracy */
if (dist > allowable_error) {
ret++;
if (ret == 1) {
sampleErrorX = i;
sampleErrorY = j;
sampleDist = dist;
}
}
}
}
SDL_UnlockSurface( surface );
SDL_UnlockSurface( referenceSurface );
/* Save test image and reference for analysis on failures */
_CompareSurfaceCount++;
if (ret != 0) {
SDLTest_LogError("Comparison of pixels with allowable error of %i failed %i times.", allowable_error, ret);
SDLTest_LogError("First detected occurrence at position %i,%i with a squared RGB-difference of %i.", sampleErrorX, sampleErrorY, sampleDist);
SDL_snprintf(imageFilename, 127, "CompareSurfaces%04d_TestOutput.bmp", _CompareSurfaceCount);
SDL_SaveBMP(surface, imageFilename);
SDL_snprintf(referenceFilename, 127, "CompareSurfaces%04d_Reference.bmp", _CompareSurfaceCount);
SDL_SaveBMP(referenceSurface, referenceFilename);
SDLTest_LogError("Surfaces from failed comparison saved as '%s' and '%s'", imageFilename, referenceFilename);
}
return ret;
}
SDL_test.h
SDLTest_CompareSurfaces
int SDLTest_CompareSurfaces(SDL_Surface *surface, SDL_Surface *referenceSurface, int allowable_error)
Compares a surface and with reference image data for equality.
Definition: SDL_test_compare.c:39
SDL_UnlockSurface
#define SDL_UnlockSurface
Definition: SDL_dynapi_overrides.h:453
Uint32
uint32_t Uint32
An unsigned 32-bit integer type.
Definition: SDL_stdinc.h:157
SDL_Surface::h
int h
Definition: SDL_surface.h:73
SDL_PixelFormat::BytesPerPixel
Uint8 BytesPerPixel
Definition: SDL_pixels.h:304
p
GLfloat GLfloat p
Definition: SDL_opengl_glext.h:11090
SDL_Surface
A collection of pixels used in software blitting.
Definition: SDL_surface.h:69
SDL_SaveBMP
#define SDL_SaveBMP(surface, file)
Definition: SDL_surface.h:199
SDL_Surface::w
int w
Definition: SDL_surface.h:73
_CompareSurfaceCount
static int _CompareSurfaceCount
Definition: SDL_test_compare.c:36
SDL_config.h
SDLTest_LogError
void SDLTest_LogError(SDL_PRINTF_FORMAT_STRING const char *fmt,...) SDL_PRINTF_VARARG_FUNC(1)
Prints given message with a timestamp in the TEST category and the ERROR priority.
Definition: SDL_test_log.c:89
SDL_Surface::pixels
void * pixels
Definition: SDL_surface.h:75
Uint8
uint8_t Uint8
An unsigned 8-bit integer type.
Definition: SDL_stdinc.h:139
SDL_GetRGBA
#define SDL_GetRGBA
Definition: SDL_dynapi_overrides.h:295
i
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:42
NULL
#define NULL
Definition: begin_code.h:143
SDL_Surface::format
SDL_PixelFormat * format
Definition: SDL_surface.h:72
SDL_LockSurface
#define SDL_LockSurface
Definition: SDL_dynapi_overrides.h:452
G
#define G(x, y, z)
Definition: SDL_test_md5.c:74
SDL_Surface::pitch
int pitch
Definition: SDL_surface.h:74
SDL_snprintf
#define SDL_snprintf
Definition: SDL_dynapi_overrides.h:46
referenceSurface
static SDL_Surface * referenceSurface
Definition: testautomation_surface.c:27
j
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int int in j)
Definition: SDL_x11sym.h:42