From e89d876fc61a17567d28ead9e0c1c5a9aa34000a Mon Sep 17 00:00:00 2001
From: Markus Kauppila <markus.kauppila@gmail.com>
Date: Sat, 13 Aug 2011 19:00:39 +0300
Subject: [PATCH] Ported tests from "./tests/automated/render"

---
 .../tests/testdummy/testdummy.c               |   3 +-
 .../tests/testrender/testrender.c             | 788 +++++++++++++++++-
 2 files changed, 785 insertions(+), 6 deletions(-)

diff --git a/test/test-automation/tests/testdummy/testdummy.c b/test/test-automation/tests/testdummy/testdummy.c
index 2735296eb..e99b406b5 100644
--- a/test/test-automation/tests/testdummy/testdummy.c
+++ b/test/test-automation/tests/testdummy/testdummy.c
@@ -141,7 +141,6 @@ dummycase2(void *arg)
 void
 dummycase3(void *arg)
 {
-	while(0);
-	//AssertTrue(1, "Assert message");
+	AssertTrue(RandomUint8() != 100, "Value is 100");
 }
 
diff --git a/test/test-automation/tests/testrender/testrender.c b/test/test-automation/tests/testrender/testrender.c
index f5f896e0d..e1a0d0afc 100644
--- a/test/test-automation/tests/testrender/testrender.c
+++ b/test/test-automation/tests/testrender/testrender.c
@@ -9,7 +9,13 @@
 
 #include "../../include/SDL_test.h"
 
+#define SCREEN_W     80
+#define SCREEN_H     60
 
+#define FACE_W       img_face.width
+#define FACE_H       img_face.height
+
+static SDL_Renderer *renderer;
 
 /*!
  * Note: Port tests from "/test/automated/render" here
@@ -23,9 +29,31 @@ static const TestCaseReference test1 =
 static const TestCaseReference test2 =
 		(TestCaseReference){ "render_testCreateRenderer", "Tests SDL_CreateRenderer", TEST_ENABLED, 0, 0 };
 
+static const TestCaseReference test3 =
+		(TestCaseReference){ "render_testPrimitives", "Tests rendering primitives", TEST_ENABLED, 0, 0 };
+
+static const TestCaseReference test4 =
+		(TestCaseReference){ "render_testPrimitivesBlend", "Tests rendering primitives with blending", TEST_ENABLED, 0, 0 };
+
+static const TestCaseReference test5 =
+		(TestCaseReference){ "render_testBlit", "Tests blitting", TEST_ENABLED, 0, 0 };
+
+static const TestCaseReference test6 =
+		(TestCaseReference){ "render_testBlitColour", "Tests blitting with color", TEST_ENABLED, 0, 0 };
+
+static const TestCaseReference test7 =
+		(TestCaseReference){ "render_testBlitAlpha", "Tests blitting with alpha", TEST_ENABLED, 0, 0 };
+
+static const TestCaseReference test8 =
+		(TestCaseReference){ "render_testBlitBlend", "Tests blitting with blending", TEST_ENABLED, 0, 0 };
+
+
+
+
+
 /* Test suite */
 extern const TestCaseReference *testSuite[] =  {
-	&test1, &test2, NULL
+	&test1, &test2, &test3, &test4, &test5, &test6, &test7, &test8, NULL
 };
 
 TestCaseReference **QueryTestSuite() {
@@ -38,15 +66,20 @@ void
 SetUp(void *arg)
 {
   /* Start SDL. */
-  int ret = SDL_Init( SDL_INIT_VIDEO );
+  int ret = SDL_InitSubSystem( SDL_INIT_VIDEO );
   AssertTrue(ret==0, "SDL_Init(SDL_INIT_VIDEO): %s", SDL_GetError());
+
+  SDL_Window *w = SDL_CreateWindow( "title", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,
+		  80, 60, SDL_WINDOW_SHOWN );
+  //if (SDL_ATassert( "SDL_CreateWindow", w!=NULL ))
+  renderer = SDL_CreateRenderer(w, 0, 0 );
 }
                         
 void
 TearDown(void *arg)
 {
-  /* Quit SDL. */
-  SDL_Quit();
+  /* Quit SDL video */
+ SDL_QuitSubSystem(SDL_INIT_VIDEO);
 }
 
 /**
@@ -91,3 +124,750 @@ render_testCreateRenderer(void *arg)
     AssertFail("Could not create window: %s", SDL_GetError());
   }  
 }
+
+
+
+/**
+ * @brief Compares screen pixels with image pixels.
+ *
+ *    @param msg Message on failure.
+ *    @param s Image to compare against.
+ *    @return 0 on success.
+ */
+static void render_compare( const char *msg, const SurfaceImage_t *s, int allowable_error )
+{
+   int ret;
+   SDL_Rect rect;
+   Uint8 pix[4*80*60];
+   SDL_Surface *testsur;
+
+   /* Read pixels. */
+   /* Explicitly specify the rect in case the window isn't expected size... */
+   rect.x = 0;
+   rect.y = 0;
+   rect.w = 80;
+   rect.h = 60;
+   ret = SDL_RenderReadPixels(renderer, &rect, FORMAT, pix, 80*4 );
+   AssertEquals(ret, 0, "SDL_RenderReadPixels failed");
+
+   /* Create surface. */
+   testsur = SDL_CreateRGBSurfaceFrom( pix, 80, 60, 32, 80*4,
+                                       RMASK, GMASK, BMASK, AMASK);
+   AssertTrue(testsur!=NULL, "SDL_CreateRGBSurface failed");
+   /* Compare surface. */
+   ret = surface_compare( testsur, s, allowable_error );
+   AssertEquals(ret, 0, "surface_compare failed");
+
+   /* Clean up. */
+   SDL_FreeSurface( testsur );
+}
+
+/**
+ * @brief Checks to see if functionality is supported.
+ */
+static int render_isSupported( int code )
+{
+   return (code == 0);
+}
+
+
+/**
+ * @brief Test to see if we can vary the draw colour.
+ */
+static int render_hasDrawColor (void)
+{
+   int ret, fail;
+   Uint8 r, g, b, a;
+
+   fail = 0;
+
+   /* Set colour. */
+   ret = SDL_SetRenderDrawColor(renderer, 100, 100, 100, 100 );
+   if (!render_isSupported(ret))
+      fail = 1;
+   ret = SDL_GetRenderDrawColor(renderer, &r, &g, &b, &a );
+   if (!render_isSupported(ret))
+      fail = 1;
+   /* Restore natural. */
+   ret = SDL_SetRenderDrawColor(renderer, 0, 0, 0, SDL_ALPHA_OPAQUE );
+   if (!render_isSupported(ret))
+      fail = 1;
+
+   /* Something failed, consider not available. */
+   if (fail)
+      return 0;
+   /* Not set properly, consider failed. */
+   else if ((r != 100) || (g != 100) || (b != 100) || (a != 100))
+      return 0;
+   return 1;
+}
+
+
+/**
+ * @brief Test to see if we can vary the blend mode.
+ */
+static int render_hasBlendModes (void)
+{
+   int fail;
+   int ret;
+   SDL_BlendMode mode;
+
+   fail = 0;
+
+   ret = SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_BLEND );
+   if (!render_isSupported(ret))
+      fail = 1;
+   ret = SDL_GetRenderDrawBlendMode(renderer, &mode );
+   if (!render_isSupported(ret))
+      fail = 1;
+   ret = (mode != SDL_BLENDMODE_BLEND);
+   if (!render_isSupported(ret))
+      fail = 1;
+   ret = SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_ADD );
+   if (!render_isSupported(ret))
+      fail = 1;
+   ret = SDL_GetRenderDrawBlendMode(renderer, &mode );
+   if (!render_isSupported(ret))
+      fail = 1;
+   ret = (mode != SDL_BLENDMODE_ADD);
+   if (!render_isSupported(ret))
+      fail = 1;
+   ret = SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_MOD );
+   if (!render_isSupported(ret))
+      fail = 1;
+   ret = SDL_GetRenderDrawBlendMode(renderer, &mode );
+   if (!render_isSupported(ret))
+      fail = 1;
+   ret = (mode != SDL_BLENDMODE_MOD);
+   if (!render_isSupported(ret))
+      fail = 1;
+   ret = SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_NONE );
+   if (!render_isSupported(ret))
+      fail = 1;
+   ret = SDL_GetRenderDrawBlendMode(renderer, &mode );
+   if (!render_isSupported(ret))
+      fail = 1;
+   ret = (mode != SDL_BLENDMODE_NONE);
+   if (!render_isSupported(ret))
+      fail = 1;
+
+   return !fail;
+}
+
+
+/**
+ * @brief Loads the test face.
+ */
+static SDL_Texture * render_loadTestFace (void)
+{
+   SDL_Surface *face;
+   SDL_Texture *tface;
+
+   /* Create face surface. */
+   face = SDL_CreateRGBSurfaceFrom( (void*)img_face.pixel_data,
+         img_face.width, img_face.height, 32, img_face.width*4,
+#if (SDL_BYTEORDER == SDL_BIG_ENDIAN)
+         0xff000000, /* Red bit mask. */
+         0x00ff0000, /* Green bit mask. */
+         0x0000ff00, /* Blue bit mask. */
+         0x000000ff /* Alpha bit mask. */
+#else
+         0x000000ff, /* Red bit mask. */
+         0x0000ff00, /* Green bit mask. */
+         0x00ff0000, /* Blue bit mask. */
+         0xff000000 /* Alpha bit mask. */
+#endif
+         );
+   if (face == NULL)
+      return 0;
+   tface = SDL_CreateTextureFromSurface(renderer, face);
+   SDL_FreeSurface(face);
+
+   return tface;
+}
+
+
+/**
+ * @brief Test to see if can set texture colour mode.
+ */
+static int render_hasTexColor (void)
+{
+   int fail;
+   int ret;
+   SDL_Texture *tface;
+   Uint8 r, g, b;
+
+   /* Get test face. */
+   tface = render_loadTestFace();
+   if (tface == 0)
+      return 0;
+
+   /* See if supported. */
+   fail = 0;
+   ret = SDL_SetTextureColorMod( tface, 100, 100, 100 );
+   if (!render_isSupported(ret))
+      fail = 1;
+   ret = SDL_GetTextureColorMod( tface, &r, &g, &b );
+   if (!render_isSupported(ret))
+      fail = 1;
+
+   /* Clean up. */
+   SDL_DestroyTexture( tface );
+
+   if (fail)
+      return 0;
+   else if ((r != 100) || (g != 100) || (b != 100))
+      return 0;
+   return 1;
+}
+
+
+/**
+ * @brief Test to see if we can vary the alpha of the texture.
+ */
+static int render_hasTexAlpha (void)
+{
+   int fail;
+   int ret;
+   SDL_Texture *tface;
+   Uint8 a;
+
+   /* Get test face. */
+   tface = render_loadTestFace();
+   if (tface == 0)
+      return 0;
+
+   /* See if supported. */
+   fail = 0;
+   ret = SDL_SetTextureAlphaMod( tface, 100 );
+   if (!render_isSupported(ret))
+      fail = 1;
+   ret = SDL_GetTextureAlphaMod( tface, &a );
+   if (!render_isSupported(ret))
+      fail = 1;
+
+   /* Clean up. */
+   SDL_DestroyTexture( tface );
+
+   if (fail)
+      return 0;
+   else if (a != 100)
+      return 0;
+   return 1;
+}
+
+
+/**
+ * @brief Tests the SDL primitives for rendering.
+ *
+ * \sa
+ * http://wiki.libsdl.org/moin.cgi/SDL_SetRenderDrawColor
+ * http://wiki.libsdl.org/moin.cgi/SDL_RenderFillRect
+ * http://wiki.libsdl.org/moin.cgi/SDL_RenderDrawLine
+ *
+ */
+int render_testPrimitives (void *arg)
+{
+   int ret;
+   int x, y;
+   SDL_Rect rect;
+
+
+   /* Need drawcolour or just skip test. */
+   AssertTrue(render_hasDrawColor(), "hasDrawColor");
+
+   /* Draw a rectangle. */
+   rect.x = 40;
+   rect.y = 0;
+   rect.w = 40;
+   rect.h = 80;
+
+   ret = SDL_SetRenderDrawColor(renderer, 13, 73, 200, SDL_ALPHA_OPAQUE );
+   AssertEquals(ret, 0, "SDL_SetRenderDrawColor");
+
+   ret = SDL_RenderFillRect(renderer, &rect );
+   AssertEquals(ret, 0,"SDL_RenderFillRect");
+
+   /* Draw a rectangle. */
+   rect.x = 10;
+   rect.y = 10;
+   rect.w = 60;
+   rect.h = 40;
+   ret = SDL_SetRenderDrawColor(renderer, 200, 0, 100, SDL_ALPHA_OPAQUE );
+   AssertEquals(ret, 0, "SDL_SetRenderDrawColor");
+
+   ret = SDL_RenderFillRect(renderer, &rect );
+   AssertEquals(ret, 0, "SDL_RenderFillRect");
+
+   /* Draw some points like so:
+    * X.X.X.X..
+    * .X.X.X.X.
+    * X.X.X.X.. */
+   for (y=0; y<3; y++) {
+      x = y % 2;
+      for (; x<80; x+=2) {
+         ret = SDL_SetRenderDrawColor(renderer, x*y, x*y/2, x*y/3, SDL_ALPHA_OPAQUE );
+         AssertEquals(ret, 0, "SDL_SetRenderDrawColor");
+
+         ret = SDL_RenderDrawPoint(renderer, x, y );
+         AssertEquals(ret, 0, "SDL_RenderDrawPoint");
+      }
+   }
+
+   /* Draw some lines. */
+   ret = SDL_SetRenderDrawColor(renderer, 0, 255, 0, SDL_ALPHA_OPAQUE );
+   AssertEquals(ret, 0, "SDL_SetRenderDrawColor");
+
+   ret = SDL_RenderDrawLine(renderer, 0, 30, 80, 30 );
+   AssertEquals(ret, 0, "SDL_RenderDrawLine");
+
+   ret = SDL_SetRenderDrawColor(renderer, 55, 55, 5, SDL_ALPHA_OPAQUE );
+   AssertEquals(ret, 0, "SDL_SetRenderDrawColor");
+
+   ret = SDL_RenderDrawLine(renderer, 40, 30, 40, 60 );
+   AssertEquals(ret, 0, "SDL_RenderDrawLine");
+
+   ret = SDL_SetRenderDrawColor(renderer, 5, 105, 105, SDL_ALPHA_OPAQUE );
+   AssertEquals(ret, 0, "SDL_SetRenderDrawColor");
+
+   ret = SDL_RenderDrawLine(renderer, 0, 0, 29, 29 );
+   AssertEquals(ret, 0, "SDL_RenderDrawLine");
+
+   ret = SDL_RenderDrawLine(renderer, 29, 30, 0, 59 );
+   AssertEquals(ret, 0, "SDL_RenderDrawLine");
+
+   ret = SDL_RenderDrawLine(renderer, 79, 0, 50, 29 );
+   AssertEquals(ret, 0, "SDL_RenderDrawLine");
+
+   ret = SDL_RenderDrawLine(renderer, 79, 59, 50, 30 );
+   AssertEquals(ret, 0, "SDL_RenderDrawLine");
+
+   /* See if it's the same. */
+   render_compare( "Primitives output not the same.", &img_primitives, ALLOWABLE_ERROR_OPAQUE );
+}
+
+
+/**
+ * @brief Tests the SDL primitives with alpha for rendering.
+ */
+int render_testPrimitivesBlend (void *arg)
+{
+   int ret;
+   int i, j;
+   SDL_Rect rect;
+
+   /* Need drawcolour and blendmode or just skip test. */
+   AssertTrue(render_hasDrawColor(), "render_hasDrawColor");
+   AssertTrue(render_hasBlendModes(), "render_hasDrawColor");
+
+   /* Create some rectangles for each blend mode. */
+   ret = SDL_SetRenderDrawColor(renderer, 255, 255, 255, 0 );
+   AssertEquals(ret, 0, "SDL_SetRenderDrawColor" );
+
+   ret = SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_NONE );
+   AssertEquals(ret, 0, "SDL_SetRenderDrawBlendMode" );
+
+   ret = SDL_RenderFillRect(renderer, NULL );
+   AssertEquals(ret, 0, "SDL_RenderFillRect" );
+
+   rect.x = 10;
+   rect.y = 25;
+   rect.w = 40;
+   rect.h = 25;
+   ret = SDL_SetRenderDrawColor(renderer, 240, 10, 10, 75 );
+   AssertEquals(ret, 0, "SDL_SetRenderDrawColor" );
+
+   ret = SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_ADD );
+   AssertEquals(ret, 0, "SDL_SetRenderDrawBlendMode" );
+
+   ret = SDL_RenderFillRect(renderer, &rect );
+   AssertEquals(ret, 0, "SDL_RenderFillRect" );
+
+   rect.x = 30;
+   rect.y = 40;
+   rect.w = 45;
+   rect.h = 15;
+   ret = SDL_SetRenderDrawColor(renderer, 10, 240, 10, 100 );
+   AssertEquals(ret, 0, "SDL_SetRenderDrawColor" );
+
+   ret = SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_BLEND );
+   AssertEquals(ret, 0, "SDL_SetRenderDrawBlendMode" );
+
+   ret = SDL_RenderFillRect(renderer, &rect );
+   AssertEquals(ret, 0, "SDL_RenderFillRect" );
+
+   rect.x = 25;
+   rect.y = 25;
+   rect.w = 25;
+   rect.h = 25;
+   ret = SDL_SetRenderDrawColor(renderer, 10, 10, 240, 125 );
+   AssertEquals(ret, 0, "SDL_SetRenderDrawColor" );
+
+   ret = SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_NONE );
+   AssertEquals(ret, 0, "SDL_SetRenderDrawBlendMode" );
+
+   ret = SDL_RenderFillRect(renderer, &rect );
+   AssertEquals(ret, 0, "SDL_RenderFillRect" );
+
+
+   /* Draw blended lines, lines for everyone. */
+   for (i=0; i<SCREEN_W; i+=2)  {
+      ret = SDL_SetRenderDrawColor(renderer, 60+2*i, 240-2*i, 50, 3*i );
+      AssertEquals(ret, 0, "SDL_SetRenderDrawColor" );
+
+      ret = SDL_SetRenderDrawBlendMode(renderer,(((i/2)%3)==0) ? SDL_BLENDMODE_BLEND :
+            (((i/2)%3)==1) ? SDL_BLENDMODE_ADD : SDL_BLENDMODE_NONE );
+      AssertEquals(ret, 0, "SDL_SetRenderDrawBlendMode" );
+
+      ret = SDL_RenderDrawLine(renderer, 0, 0, i, 59 );
+      AssertEquals(ret, 0, "SDL_RenderDrawLine" );
+   }
+   for (i=0; i<SCREEN_H; i+=2)  {
+      ret = SDL_SetRenderDrawColor(renderer, 60+2*i, 240-2*i, 50, 3*i );
+      AssertEquals(ret, 0, "SDL_SetRenderDrawColor" );
+
+      ret = SDL_SetRenderDrawBlendMode(renderer,(((i/2)%3)==0) ? SDL_BLENDMODE_BLEND :
+            (((i/2)%3)==1) ? SDL_BLENDMODE_ADD : SDL_BLENDMODE_NONE );
+
+      AssertEquals(ret, 0, "SDL_SetRenderDrawBlendMode" );
+
+      ret = SDL_RenderDrawLine(renderer, 0, 0, 79, i );
+
+      AssertEquals(ret, 0, "SDL_RenderDrawLine" );
+   }
+
+   /* Draw points. */
+   for (j=0; j<SCREEN_H; j+=3) {
+      for (i=0; i<SCREEN_W; i+=3) {
+         ret = SDL_SetRenderDrawColor(renderer, j*4, i*3, j*4, i*3 );
+         AssertEquals(ret, 0, "SDL_SetRenderDrawColor" );
+
+         ret = SDL_SetRenderDrawBlendMode(renderer, ((((i+j)/3)%3)==0) ? SDL_BLENDMODE_BLEND :
+               ((((i+j)/3)%3)==1) ? SDL_BLENDMODE_ADD : SDL_BLENDMODE_NONE );
+
+         AssertEquals(ret, 0, "SDL_SetRenderDrawBlendMode" );
+
+         ret = SDL_RenderDrawPoint(renderer, i, j );
+         AssertEquals(ret, 0, "SDL_RenderDrawPoint" );
+      }
+   }
+
+   /* See if it's the same. FIXME needs assert */
+   render_compare( "Blended primitives output not the same.", &img_blend, ALLOWABLE_ERROR_BLENDED );
+}
+
+
+/**
+ * @brief Tests some blitting routines.
+ */
+int
+render_testBlit(void *arg)
+{
+   int ret;
+   SDL_Rect rect;
+   SDL_Texture *tface;
+   int i, j, ni, nj;
+
+
+   /* Need drawcolour or just skip test. */
+   AssertTrue(render_hasDrawColor(), "render_hasDrawColor)");
+
+   /* Create face surface. */
+   tface = render_loadTestFace();
+   AssertTrue(tface != 0,  "render_loadTestFace()");
+
+   /* Constant values. */
+   rect.w = img_face.width;
+   rect.h = img_face.height;
+   ni     = SCREEN_W - img_face.width;
+   nj     = SCREEN_H - img_face.height;
+
+   /* Loop blit. */
+   for (j=0; j <= nj; j+=4) {
+      for (i=0; i <= ni; i+=4) {
+         /* Blitting. */
+         rect.x = i;
+         rect.y = j;
+         ret = SDL_RenderCopy(renderer, tface, NULL, &rect );
+         AssertEquals(ret, 0, "SDL_RenderCopy");
+      }
+   }
+
+   /* Clean up. */
+   SDL_DestroyTexture( tface );
+
+   /* See if it's the same. FIXME needs assert */
+   render_compare( "Blit output not the same.", &img_blit, ALLOWABLE_ERROR_OPAQUE );
+}
+
+/**
+ * @brief Blits doing colour tests.
+ */
+int
+render_testBlitColour (void *arg)
+{
+   int ret;
+   SDL_Rect rect;
+   SDL_Texture *tface;
+   int i, j, ni, nj;
+
+   /* Create face surface. */
+   tface = render_loadTestFace();
+
+   AssertTrue(tface != 0, "render_loadTestFace()");
+
+   /* Constant values. */
+   rect.w = img_face.width;
+   rect.h = img_face.height;
+   ni     = SCREEN_W - img_face.width;
+   nj     = SCREEN_H - img_face.height;
+
+   /* Test blitting with colour mod. */
+   for (j=0; j <= nj; j+=4) {
+      for (i=0; i <= ni; i+=4) {
+         /* Set colour mod. */
+         ret = SDL_SetTextureColorMod( tface, (255/nj)*j, (255/ni)*i, (255/nj)*j );
+         AssertEquals(ret, 0, "SDL_SetTextureColorMod");
+
+         /* Blitting. */
+         rect.x = i;
+         rect.y = j;
+         ret = SDL_RenderCopy(renderer, tface, NULL, &rect );
+         AssertEquals(ret, 0, "SDL_RenderCopy");
+      }
+   }
+
+   /* Clean up. */
+   SDL_DestroyTexture( tface );
+
+   /* See if it's the same. */
+   render_compare( "Blit output not the same (using SDL_SetTextureColorMod).",
+            &img_blitColour, ALLOWABLE_ERROR_OPAQUE );
+}
+
+/**
+ * @brief Tests blitting with alpha.
+ */
+int
+render_testBlitAlpha (void *arg)
+{
+   int ret;
+   SDL_Rect rect;
+   SDL_Texture *tface;
+   int i, j, ni, nj;
+
+   /* Need alpha or just skip test. */
+   AssertTrue(render_hasTexAlpha(), "render_hasTexAlpha");
+
+   /* Create face surface. */
+   tface = render_loadTestFace();
+   AssertTrue(tface != 0, "render_loadTestFace()");
+
+   /* Constant values. */
+   rect.w = img_face.width;
+   rect.h = img_face.height;
+   ni     = SCREEN_W - img_face.width;
+   nj     = SCREEN_H - img_face.height;
+
+   /* Test blitting with alpha mod. */
+   for (j=0; j <= nj; j+=4) {
+      for (i=0; i <= ni; i+=4) {
+         /* Set alpha mod. */
+         ret = SDL_SetTextureAlphaMod( tface, (255/ni)*i );
+         AssertEquals(ret, 0, "SDL_SetTextureAlphaMod");
+
+         /* Blitting. */
+         rect.x = i;
+         rect.y = j;
+         ret = SDL_RenderCopy(renderer, tface, NULL, &rect );
+         AssertEquals(ret, 0, "SDL_RenderCopy");
+      }
+   }
+
+   /* Clean up. */
+   SDL_DestroyTexture( tface );
+
+   /* See if it's the same. */
+   render_compare( "Blit output not the same (using SDL_SetSurfaceAlphaMod).",
+            &img_blitAlpha, ALLOWABLE_ERROR_BLENDED );
+}
+
+/**
+ * @brief Clears the screen.
+ *
+ * @note We don't test for errors, but they shouldn't happen.
+ */
+static int render_clearScreen (void)
+{
+   int ret;
+
+   /* Set colour. */
+   ret = SDL_SetRenderDrawColor(renderer, 0, 0, 0, SDL_ALPHA_OPAQUE );
+   /*
+   if (SDL_ATassert( "SDL_SetRenderDrawColor", ret == 0))
+      return -1;
+   */
+
+   /* Clear screen. */
+   ret = SDL_RenderFillRect(renderer, NULL );
+   /*
+   if (SDL_ATassert( "SDL_RenderFillRect", ret == 0))
+      return -1;
+   */
+
+   /* Set defaults. */
+   ret = SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_NONE );
+   /*
+   if (SDL_ATassert( "SDL_SetRenderDrawBlendMode", ret == 0))
+      return -1;
+   */
+   ret = SDL_SetRenderDrawColor(renderer, 255, 255, 255, SDL_ALPHA_OPAQUE );
+   /*
+   if (SDL_ATassert( "SDL_SetRenderDrawColor", ret == 0))
+      return -1;
+   */
+
+   return 0;
+}
+
+/**
+ * @brief Tests a blend mode. Helper.
+ */
+void
+render_testBlitBlendMode( SDL_Texture * tface, int mode )
+{
+   int ret;
+   int i, j, ni, nj;
+   SDL_Rect rect;
+
+   /* Clear surface. */
+   if (render_clearScreen())
+      return -1;
+
+   /* Steps to take. */
+   ni     = SCREEN_W - FACE_W;
+   nj     = SCREEN_H - FACE_H;
+
+   /* Constant values. */
+   rect.w = FACE_W;
+   rect.h = FACE_H;
+
+   /* Test blend mode. */
+   for (j=0; j <= nj; j+=4) {
+      for (i=0; i <= ni; i+=4) {
+         /* Set blend mode. */
+         ret = SDL_SetTextureBlendMode( tface, mode );
+         AssertEquals(ret, 0, "SDL_SetTextureBlendMode");
+
+         /* Blitting. */
+         rect.x = i;
+         rect.y = j;
+         ret = SDL_RenderCopy(renderer, tface, NULL, &rect );
+         AssertEquals(ret, 0, "SDL_RenderCopy");
+      }
+   }
+}
+
+
+
+
+/**
+ * @brief Tests some more blitting routines.
+ */
+int
+render_testBlitBlend (void *arg)
+{
+   int ret;
+   SDL_Rect rect;
+   SDL_Texture *tface;
+   int i, j, ni, nj;
+   int mode;
+
+
+   AssertTrue(render_hasBlendModes(), "render_hasBlendModes");
+   AssertTrue(render_hasTexColor(), "render_hasTexColor");
+   AssertTrue(render_hasTexAlpha(), "render_hasTexAlpha");
+
+   /* Create face surface. */
+   tface = render_loadTestFace();
+   AssertTrue(tface != 0, "render_loadTestFace()");
+
+   /* Steps to take. */
+   ni     = SCREEN_W - FACE_W;
+   nj     = SCREEN_H - FACE_H;
+
+   /* Constant values. */
+   rect.w = img_face.width;
+   rect.h = img_face.height;
+
+   /* Set alpha mod. */
+   ret = SDL_SetTextureAlphaMod( tface, 100 );
+   AssertEquals(ret, 0, "SDL_SetTextureAlphaMod");
+
+   /* Test None. */
+   render_testBlitBlendMode( tface, SDL_BLENDMODE_NONE );
+   /* See if it's the same. */
+   render_compare( "Blit blending output not the same (using SDL_BLENDMODE_NONE).",
+            &img_blendNone, ALLOWABLE_ERROR_OPAQUE ); //FIXME add assert
+
+
+   /* Test Blend. */
+   render_testBlitBlendMode( tface, SDL_BLENDMODE_BLEND );
+   render_compare( "Blit blending output not the same (using SDL_BLENDMODE_BLEND).",
+            &img_blendBlend, ALLOWABLE_ERROR_BLENDED ); //FIXME add assert
+
+
+   /* Test Add. */
+   render_testBlitBlendMode( tface, SDL_BLENDMODE_ADD );
+
+  render_compare( "Blit blending output not the same (using SDL_BLENDMODE_ADD).",
+            &img_blendAdd, ALLOWABLE_ERROR_BLENDED ); //FIXME add assert
+
+   /* Test Mod. */
+   render_testBlitBlendMode( tface, SDL_BLENDMODE_MOD);
+
+   render_compare( "Blit blending output not the same (using SDL_BLENDMODE_MOD).",
+            &img_blendMod, ALLOWABLE_ERROR_BLENDED );
+
+   /* Clear surface. */
+   render_clearScreen();
+
+   /* Loop blit. */
+   for (j=0; j <= nj; j+=4) {
+      for (i=0; i <= ni; i+=4) {
+
+         /* Set colour mod. */
+         ret = SDL_SetTextureColorMod( tface, (255/nj)*j, (255/ni)*i, (255/nj)*j );
+         AssertEquals(ret, 0, "SDL_SetTextureColorMod");
+
+         /* Set alpha mod. */
+         ret = SDL_SetTextureAlphaMod( tface, (100/ni)*i );
+         AssertEquals(ret, 0, "SDL_SetTextureAlphaMod");
+
+         /* Crazy blending mode magic. */
+         mode = (i/4*j/4) % 4;
+         if (mode==0) mode = SDL_BLENDMODE_NONE;
+         else if (mode==1) mode = SDL_BLENDMODE_BLEND;
+         else if (mode==2) mode = SDL_BLENDMODE_ADD;
+         else if (mode==3) mode = SDL_BLENDMODE_MOD;
+         ret = SDL_SetTextureBlendMode( tface, mode );
+         AssertEquals(ret, 0, "SDL_SetTextureBlendMode");
+
+         /* Blitting. */
+         rect.x = i;
+         rect.y = j;
+         ret = SDL_RenderCopy(renderer, tface, NULL, &rect );
+         AssertEquals(ret, 0, "SDL_RenderCopy");
+      }
+   }
+
+   /* Clean up. */
+   SDL_DestroyTexture( tface );
+
+   /* Check to see if matches. */
+   render_compare( "Blit blending output not the same (using SDL_BLENDMODE_*).",
+            &img_blendAll, ALLOWABLE_ERROR_BLENDED); // FIXME add assert
+}
+
+
+