add VisualFromRGBxPacked unit test

src/lib/visual.c

@@ -655,7 +655,7 @@ ncvisual* ncvisual_from_rgb_loose(const void* rgba, int rows, int rowstride,
 //fprintf(stderr, "ROWS: %d STRIDE: %d (%d) COLS: %d %08x\n", ncv->pixy, ncv->rowstride, ncv->rowstride / 4, cols, data[ncv->rowstride * y / 4]);
       memcpy(data + (ncv->rowstride * y) / 4, (const char*)rgba + rowstride * y, rowstride);
       for(int x = 0 ; x < cols ; ++x){
-        ncpixel_set_a(&data[y * cols + x], alpha);
+        ncpixel_set_a(&data[y * ncv->rowstride / 4 + x], alpha);
       }
     }
     ncvisual_set_data(ncv, data, true);

src/tests/visual.cpp

@@ -12,7 +12,7 @@ TEST_CASE("Visual") {
 
   // check that we properly populate RGB + A -> RGBA
   SUBCASE("VisualFromRGBPacked") {
-    unsigned char rgb[13] = "\x88\x77\x66\x55\x44\x33\x22\x11\x00\x99\xaa\xbb";
+    unsigned char rgb[] = "\x88\x77\x66\x55\x44\x33\x22\x11\x00\x99\xaa\xbb";
     unsigned char alpha = 0xff;
     auto ncv = ncvisual_from_rgb_packed(rgb, 2, 6, 2, alpha);
     REQUIRE(nullptr != ncv);
@@ -20,7 +20,6 @@ TEST_CASE("Visual") {
       for(int x = 0 ; x < 2 ; ++x){
         uint32_t p;
         CHECK(0 == ncvisual_at_yx(ncv, y, x, &p));
-fprintf(stderr, "rgba: 0x%02x 0x%02x 0x%02x 0x%02x\n", ncpixel_r(p), ncpixel_g(p), ncpixel_b(p), ncpixel_a(p));
         CHECK(ncpixel_r(p) == rgb[y * 6 + x * 3]);
         CHECK(ncpixel_g(p) == rgb[y * 6 + x * 3 + 1]);
         CHECK(ncpixel_b(p) == rgb[y * 6 + x * 3 + 2]);
@@ -29,6 +28,24 @@ fprintf(stderr, "rgba: 0x%02x 0x%02x 0x%02x 0x%02x\n", ncpixel_r(p), ncpixel_g(p
     }
   }
 
+  // check that we properly populate RGBx + A -> RGBA
+  SUBCASE("VisualFromRGBxPacked") {
+    unsigned char rgb[] = "\x88\x77\x66\x12\x55\x44\x33\x10\x22\x11\x00\xdd\x99\xaa\xbb\xcc";
+    unsigned char alpha = 0xff;
+    auto ncv = ncvisual_from_rgb_loose(rgb, 2, 8, 2, alpha);
+    REQUIRE(nullptr != ncv);
+    for(int y = 0 ; y < 2 ; ++y){
+      for(int x = 0 ; x < 2 ; ++x){
+        uint32_t p;
+        CHECK(0 == ncvisual_at_yx(ncv, y, x, &p));
+        CHECK(ncpixel_r(p) == rgb[y * 8 + x * 4]);
+        CHECK(ncpixel_g(p) == rgb[y * 8 + x * 4 + 1]);
+        CHECK(ncpixel_b(p) == rgb[y * 8 + x * 4 + 2]);
+        CHECK(ncpixel_a(p) == alpha);
+      }
+    }
+  }
+
   // check that NCVISUAL_OPTION_HORALIGNED works in all three cases
   SUBCASE("VisualAligned") {
     const uint32_t pixels[4] = { htole(0xffff0000), htole(0xff00ff00), htole(0xff0000ff), htole(0xffffffff) };