Shaders: got rid of Point2D/3D in positions in favor of Vector2/Vector3.

Originally it was for more convenient usage of homogeneous coordinates
in shaders themselves, but it is actually not needed:
 * When passing three-component vector (3D position) to `vec4`, the last
   coordinate is implicitly set to `1`, thus there is no need to pass it
   explicitly in each attribute.
 * On the other hand, when passing three-component vector (2D position
   in homogeneous coordinates) to `vec3` with Z explicitly set to `1`,
   it still needs some swizzle magic to extend it to `vec4` gl_Position.
   Passing it as two-component vector results in nearly the same magic
   while saving precious memory.

src/Shaders/AbstractTextShader.h

@@ -33,7 +33,7 @@ namespace Magnum { namespace Shaders {
 template<std::uint8_t dimensions> class AbstractTextShader: public AbstractShaderProgram {
     public:
         /** @brief Vertex position */
-        typedef Attribute<0, typename DimensionTraits<dimensions>::PointType> Position;
+        typedef Attribute<0, typename DimensionTraits<dimensions>::VectorType> Position;
 
         /** @brief Texture coordinates */
         typedef Attribute<1, Vector2> TextureCoordinates;

src/Shaders/FlatShader.h

@@ -38,7 +38,7 @@ Draws whole mesh with one color.
 template<std::uint8_t dimensions> class MAGNUM_SHADERS_EXPORT FlatShader: public AbstractShaderProgram {
     public:
         /** @brief Vertex position */
-        typedef Attribute<0, typename DimensionTraits<dimensions>::PointType> Position;
+        typedef Attribute<0, typename DimensionTraits<dimensions>::VectorType> Position;
 
         explicit FlatShader();
 

src/Shaders/FlatShader2D.vert

@@ -9,11 +9,11 @@ uniform highp mat3 transformationProjectionMatrix;
 #endif
 
 #ifdef EXPLICIT_ATTRIB_LOCATION
-layout(location = 0) in highp vec3 position;
+layout(location = 0) in highp vec2 position;
 #else
-in highp vec3 position;
+in highp vec2 position;
 #endif
 
 void main() {
-    gl_Position.xywz = vec4(transformationProjectionMatrix*position, 0.0);
+    gl_Position.xywz = vec4(transformationProjectionMatrix*vec3(position, 1.0), 0.0);
 }

src/Shaders/PhongShader.h

@@ -35,7 +35,7 @@ otherwise falls back to GLSL 1.20.
 */
 class MAGNUM_SHADERS_EXPORT PhongShader: public AbstractShaderProgram {
     public:
-        typedef Attribute<0, Point3D> Position; /**< @brief Vertex position */
+        typedef Attribute<0, Vector3> Position; /**< @brief Vertex position */
         typedef Attribute<1, Vector3> Normal;   /**< @brief Normal direction */
 
         explicit PhongShader();

src/Shaders/TextShader2D.vert

@@ -10,16 +10,16 @@ uniform highp mat3 transformationProjectionMatrix;
 #endif
 
 #ifdef EXPLICIT_ATTRIB_LOCATION
-layout(location = 0) in highp vec3 position;
+layout(location = 0) in highp vec2 position;
 layout(location = 1) in mediump vec2 textureCoordinates;
 #else
-in highp vec3 position;
+in highp vec2 position;
 in mediump vec2 textureCoordinates;
 #endif
 
 out vec2 fragmentTextureCoordinates;
 
 void main() {
-    gl_Position.xywz = vec4(transformationProjectionMatrix*position, 0.0);
+    gl_Position.xywz = vec4(transformationProjectionMatrix*vec3(position, 1.0), 0.0);
     fragmentTextureCoordinates = textureCoordinates;
 }

src/Shaders/VertexColorShader.h

@@ -38,7 +38,7 @@ Draws vertex-colored mesh.
 template<std::uint8_t dimensions> class MAGNUM_SHADERS_EXPORT VertexColorShader: public AbstractShaderProgram {
     public:
         /** @brief Vertex position */
-        typedef Attribute<0, typename DimensionTraits<dimensions>::PointType> Position;
+        typedef Attribute<0, typename DimensionTraits<dimensions>::VectorType> Position;
 
         /** @brief Vertex color */
         typedef Attribute<1, Color3<>> Color;

src/Shaders/VertexColorShader2D.vert

@@ -10,16 +10,16 @@ uniform highp mat3 transformationProjectionMatrix;
 #endif
 
 #ifdef EXPLICIT_ATTRIB_LOCATION
-layout(location = 0) in highp vec3 position;
+layout(location = 0) in highp vec2 position;
 layout(location = 1) in lowp vec3 color;
 #else
-in highp vec3 position;
+in highp vec2 position;
 in lowp vec3 color;
 #endif
 
 out lowp vec3 interpolatedColor;
 
 void main() {
-    gl_Position.xywz = vec4(transformationProjectionMatrix*position, 0.0);
+    gl_Position.xywz = vec4(transformationProjectionMatrix*vec3(position, 1.0), 0.0);
     interpolatedColor = color;
 }