Add sprite, draw_op and vertex classes

projectfiles/VC14/wesnoth.vcxproj

@@ -2551,6 +2551,7 @@
       <ObjectFileName Condition="'$(Configuration)|$(Platform)'=='Test_Debug|Win32'">$(IntDir)OGL\</ObjectFileName>
       <ObjectFileName Condition="'$(Configuration)|$(Platform)'=='Test_Release|Win32'">$(IntDir)OGL\</ObjectFileName>
     </ClCompile>
+    <ClCompile Include="..\..\src\ogl\sprite.cpp" />
     <ClCompile Include="..\..\src\ogl\texture.cpp">
       <ObjectFileName Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">$(IntDir)OGL\</ObjectFileName>
       <ObjectFileName Condition="'$(Configuration)|$(Platform)'=='ReleaseDEBUG|Win32'">$(IntDir)OGL\</ObjectFileName>
@@ -3909,8 +3910,11 @@
     <ClInclude Include="..\..\src\multiplayer_error_codes.hpp" />
     <ClInclude Include="..\..\src\network_asio.hpp" />
     <ClInclude Include="..\..\src\ogl\context.hpp" />
+    <ClInclude Include="..\..\src\ogl\draw_op.hpp" />
+    <ClInclude Include="..\..\src\ogl\sprite.hpp" />
     <ClInclude Include="..\..\src\ogl\texture.hpp" />
     <ClInclude Include="..\..\src\ogl\utils.hpp" />
+    <ClInclude Include="..\..\src\ogl\vertex.hpp" />
     <ClInclude Include="..\..\src\overlay.hpp" />
     <ClInclude Include="..\..\src\pathfind\pathfind.hpp" />
     <ClInclude Include="..\..\src\pathfind\teleport.hpp" />

projectfiles/VC14/wesnoth.vcxproj.filters

@@ -1558,6 +1558,9 @@
     <ClCompile Include="..\..\src\ogl\texture.cpp">
       <Filter>OGL</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\src\ogl\sprite.cpp">
+      <Filter>OGL</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\..\src\addon\client.hpp">
@@ -3025,6 +3028,15 @@
     <ClInclude Include="..\..\src\ogl\texture.hpp">
       <Filter>OGL</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\src\ogl\vertex.hpp">
+      <Filter>OGL</Filter>
+    </ClInclude>
+    <ClInclude Include="..\..\src\ogl\draw_op.hpp">
+      <Filter>OGL</Filter>
+    </ClInclude>
+    <ClInclude Include="..\..\src\ogl\sprite.hpp">
+      <Filter>OGL</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <CustomBuild Include="..\..\src\tests\test_sdl_utils.hpp">

source_lists/libwesnoth_sdl

@@ -1,4 +1,5 @@
 ogl/context.cpp
+ogl/sprite.cpp
 ogl/texture.cpp
 ogl/utils.cpp
 sdl/exception.cpp

src/ogl/draw_op.hpp

@@ -0,0 +1,32 @@
+/*
+   Copyright (C) 2018 by Jyrki Vesterinen <sandgtx@gmail.com>
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY.
+
+   See the COPYING file for more details.
+*/
+
+#pragma once
+
+#include "ogl/vertex.hpp"
+
+#include <GL/glew.h>
+
+#include <array>
+
+namespace gl
+{
+/** Represents a single draw operation.
+The shape is always a triangle. */
+struct draw_op
+{
+	std::array<vertex, 3> vertices;
+	GLuint texture_name;
+};
+
+}

src/ogl/sprite.cpp

@@ -0,0 +1,30 @@
+/*
+   Copyright (C) 2018 by Jyrki Vesterinen <sandgtx@gmail.com>
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY.
+
+   See the COPYING file for more details.
+*/
+
+#include "ogl/sprite.hpp"
+
+namespace gl
+{
+
+void sprite::normalize_coordinates(const std::pair<int, int>& texture_size)
+{
+	x_min = static_cast<float>(x_min_px) / static_cast<float>(texture_size.first);
+	x_max = static_cast<float>(x_max_px) / static_cast<float>(texture_size.first);
+	y_min = static_cast<float>(y_min_px) / static_cast<float>(texture_size.second);
+	y_max = static_cast<float>(y_max_px) / static_cast<float>(texture_size.second);
+
+	half_width = (x_max_px - x_min_px) / 2.0f;
+	half_height = (y_max_px - y_min_px) / 2.0f;
+}
+
+}

src/ogl/sprite.hpp

@@ -0,0 +1,111 @@
+/*
+   Copyright (C) 2018 by Jyrki Vesterinen <sandgtx@gmail.com>
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY.
+
+   See the COPYING file for more details.
+*/
+
+#pragma once
+
+#include "ogl/draw_op.hpp"
+#include "ogl/texture.hpp"
+
+#include <GL/glew.h>
+
+#include <utility>
+
+namespace gl
+{
+
+class sprite
+{
+public:
+	/** Texture name. */
+	const GLuint texture_name;
+
+	/** X coordinate of left edge. Normalized to the range [0, 1]. */
+	float x_min;
+	/** X coordinate of right edge. Normalized to the range [0, 1]. */
+	float x_max;
+	/** Y coordinate of bottom edge. Normalized to the range [0, 1]. */
+	float y_min;
+	/** Y coordinate of top edge. Normalized to the range [0, 1]. */
+	float y_max;
+
+	/** X coordinate of left edge as pixels. */
+	unsigned int x_min_px;
+	/** X coordinate of right edge as pixels. */
+	unsigned int x_max_px;
+	/** Y coordinate of bottom edge as pixels. */
+	unsigned int y_min_px;
+	/** Y coordinate of top edge as pixels. */
+	unsigned int y_max_px;
+
+	/** Half of the width of the sprite, in pixels. */
+	float half_width;
+
+	/** Half of the height of the sprite, in pixels. */
+	float half_height;
+
+	/** Constructor. */
+	sprite(const texture& tex) : texture_name(tex.get_name())
+	{
+
+	}
+
+	/** Calculates normalized texture coordinates from pixel coordinates and texture size. */
+	void normalize_coordinates(const std::pair<int, int>& texture_size);
+
+	/** Generates draw operations which draw the sprite.
+	The sprite is anchored to center.
+	@param x X coordinate for center of the sprite.
+	@param y Y coordinate for center of the sprite.
+	@param out An output iterator for the container where the draw operations will be pushed.
+	@todo Scaling support. */
+	template<typename T>
+	void to_draw_ops(float x, float y, T out) const
+	{
+		draw_op op;
+		op.texture_name = texture_name;
+
+		op.vertices[0].x = x - half_width;
+		op.vertices[0].y = y - half_height;
+		op.vertices[1].x = x + half_width;
+		op.vertices[1].y = y - half_height;
+		op.vertices[2].x = x + half_width;
+		op.vertices[2].y = y + half_height;
+		op.vertices[0].u = x_min;
+		op.vertices[0].v = y_min;
+		op.vertices[1].u = x_max;
+		op.vertices[1].v = y_min;
+		op.vertices[2].u = x_max;
+		op.vertices[2].v = y_max;
+
+		// Assigning to the iterator pushes the draw operation.
+		// It pushes a copy, allowing us to modify the original.
+		out = op;
+
+		op.vertices[0].x = x - half_width;
+		op.vertices[0].y = y - half_height;
+		op.vertices[1].x = x + half_width;
+		op.vertices[1].y = y + half_height;
+		op.vertices[2].x = x - half_width;
+		op.vertices[2].y = y + half_height;
+		op.vertices[0].u = x_min;
+		op.vertices[0].v = y_min;
+		op.vertices[1].u = x_max;
+		op.vertices[1].v = y_max;
+		op.vertices[2].u = x_min;
+		op.vertices[2].v = y_max;
+
+		out = op;
+	}
+};
+
+}

src/ogl/vertex.hpp

@@ -0,0 +1,31 @@
+/*
+   Copyright (C) 2018 by Jyrki Vesterinen <sandgtx@gmail.com>
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY.
+
+   See the COPYING file for more details.
+*/
+
+#pragma once
+
+#include <GL/glew.h>
+
+namespace gl
+{
+
+struct vertex
+{
+	// Vertex coordinates
+	GLfloat x;
+	GLfloat y;
+	// Texture coordinates
+	GLfloat u;
+	GLfloat v;
+};
+
+}