Primitives: fix and make gradient function params consistent.

doc/snippets/MagnumPrimitives.cpp

@@ -33,21 +33,23 @@ using namespace Magnum;
 
 int main() {
 {
-Color4 colorA, colorB;
+Color4 colorLeft, colorRight, colorBottom, colorTop;
 /* [gradient2DHorizontal] */
-Primitives::gradient2D({-1.0f, 0.0f}, colorA, {1.0f, 0.0f}, colorB);
+Primitives::gradient2D({-1.0f, 0.0f}, colorLeft, {1.0f, 0.0f}, colorRight);
 /* [gradient2DHorizontal] */
 
 /* [gradient2DVertical] */
-Primitives::gradient2D({0.0f, -1.0f}, colorA, {0.0f, 1.0f}, colorB);
+Primitives::gradient2D({0.0f, -1.0f}, colorBottom, {0.0f, 1.0f}, colorTop);
 /* [gradient2DVertical] */
 
 /* [gradient3DHorizontal] */
-Primitives::gradient3D({-1.0f, 0.0f, 0.0f}, colorA, {1.0f, 0.0f, 0.0f}, colorB);
+Primitives::gradient3D({-1.0f, 0.0f, 0.0f}, colorLeft,
+                       { 1.0f, 0.0f, 0.0f}, colorRight);
 /* [gradient3DHorizontal] */
 
 /* [gradient3DVertical] */
-Primitives::gradient3D({0.0f, -1.0f, 0.0f}, colorA, {0.0f, 1.0f, 0.0f}, colorB);
+Primitives::gradient3D({0.0f, -1.0f, 0.0f}, colorBottom,
+                       {0.0f,  1.0f, 0.0f}, colorTop);
 /* [gradient3DVertical] */
 }
 

src/Magnum/Primitives/Gradient.cpp

@@ -54,12 +54,12 @@ Trade::MeshData2D gradient2D(const Vector2& a, const Color4& colorA, const Vecto
     return Trade::MeshData2D{MeshPrimitive::TriangleStrip, {}, {std::move(positions)}, {}, {std::move(colors)}, nullptr};
 }
 
-Trade::MeshData2D gradient2DHorizontal(const Color4& colorA, const Color4& colorB) {
-    return Primitives::gradient2D({-1.0f, 0.0f}, colorA, {1.0f, 0.0f}, colorB);
+Trade::MeshData2D gradient2DHorizontal(const Color4& colorLeft, const Color4& colorRight) {
+    return Primitives::gradient2D({-1.0f, 0.0f}, colorLeft, {1.0f, 0.0f}, colorRight);
 }
 
-Trade::MeshData2D gradient2DVertical(const Color4& colorA, const Color4& colorB) {
-    return Primitives::gradient2D({0.0f, -1.0f}, colorA, {0.0f, 1.0f}, colorB);
+Trade::MeshData2D gradient2DVertical(const Color4& colorBottom, const Color4& colorTop) {
+    return Primitives::gradient2D({0.0f, -1.0f}, colorBottom, {0.0f, 1.0f}, colorTop);
 }
 
 Trade::MeshData3D gradient3D(const Vector3& a, const Color4& colorA, const Vector3& b, const Color4& colorB) {
@@ -88,12 +88,12 @@ Trade::MeshData3D gradient3D(const Vector3& a, const Color4& colorA, const Vecto
     }}, {}, {std::move(colors)}, nullptr};
 }
 
-Trade::MeshData3D gradient3DHorizontal(const Color4& colorA, const Color4& colorB) {
-    return Primitives::gradient3D({-1.0f, 0.0f, 0.0f}, colorA, {1.0f, 0.0f, 0.0f}, colorB);
+Trade::MeshData3D gradient3DHorizontal(const Color4& colorLeft, const Color4& colorRight) {
+    return Primitives::gradient3D({-1.0f, 0.0f, 0.0f}, colorLeft, {1.0f, 0.0f, 0.0f}, colorRight);
 }
 
-Trade::MeshData3D gradient3DVertical(const Color4& colorA, const Color4& colorB) {
-    return Primitives::gradient3D({0.0f, -1.0f, 0.0f}, colorA, {0.0f, 1.0f, 0.0f}, colorB);
+Trade::MeshData3D gradient3DVertical(const Color4& colorBottom, const Color4& colorTop) {
+    return Primitives::gradient3D({0.0f, -1.0f, 0.0f}, colorBottom, {0.0f, 1.0f, 0.0f}, colorTop);
 }
 
 }}

src/Magnum/Primitives/Gradient.h

@@ -60,7 +60,7 @@ Equivalent to calling @ref gradient2D() like this:
 
 @see @ref gradient2DVertical(), @ref gradient3DHorizontal(), @ref squareSolid()
 */
-MAGNUM_PRIMITIVES_EXPORT Trade::MeshData2D gradient2DHorizontal(const Color4& colorLeft, const Color4& color);
+MAGNUM_PRIMITIVES_EXPORT Trade::MeshData2D gradient2DHorizontal(const Color4& colorLeft, const Color4& colorRight);
 
 /**
 @brief 2D square with a vertical gradient
@@ -101,7 +101,7 @@ Equivalent to calling @ref gradient3D() like this:
 
 @see @ref gradient3DVertical(), @ref gradient2DHorizontal(), @ref planeSolid()
 */
-MAGNUM_PRIMITIVES_EXPORT Trade::MeshData3D gradient3DHorizontal(const Color4& colorLeft, const Color4& color);
+MAGNUM_PRIMITIVES_EXPORT Trade::MeshData3D gradient3DHorizontal(const Color4& colorLeft, const Color4& colorRight);
 
 /**
 @brief 3D plane with a vertical gradient