1 files changed, 120 insertions, 0 deletions
diff --git a/vcl/inc/opengl/VertexUtils.hxx b/vcl/inc/opengl/VertexUtils.hxx
new file mode 100644
index 000000000..910b8725a
--- /dev/null
+++ b/vcl/inc/opengl/VertexUtils.hxx
@@ -0,0 +1,120 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ */
+
+#ifndef INCLUDED_VCL_INC_OPENGL_VERTEXUTILS_H
+#define INCLUDED_VCL_INC_OPENGL_VERTEXUTILS_H
+
+#include <basegfx/numeric/ftools.hxx>
+#include <epoxy/gl.h>
+#include <glm/gtx/norm.hpp>
+#include <tools/color.hxx>
+#include <vector>
+
+namespace vcl
+{
+namespace vertex
+{
+
+template<GLenum TYPE>
+inline void addRectangle(std::vector<GLfloat>& rVertices, GLfloat x1, GLfloat y1, GLfloat x2, GLfloat y2);
+
+template<>
+inline void addRectangle<GL_TRIANGLES>(std::vector<GLfloat>& rVertices, GLfloat x1, GLfloat y1, GLfloat x2, GLfloat y2)
+{
+    rVertices.insert(rVertices.end(), {
+        x1, y1, x2, y1, x1, y2,
+        x1, y2, x2, y1, x2, y2
+    });
+}
+
+template<>
+inline void addRectangle<GL_TRIANGLE_FAN>(std::vector<GLfloat>& rVertices, GLfloat x1, GLfloat y1, GLfloat x2, GLfloat y2)
+{
+    rVertices.insert(rVertices.end(), {
+        x1, y2, x1, y1,
+        x2, y1, x2, y2
+    });
+}
+
+inline void createColor(Color nColor, GLfloat fTransparency, GLubyte& nR, GLubyte& nG, GLubyte& nB, GLubyte& nA)
+{
+    nR = nColor.GetRed();
+    nG = nColor.GetGreen();
+    nB = nColor.GetBlue();
+    nA = (1.0f - fTransparency) * 255.0f;
+}
+
+template<GLenum TYPE>
+inline void addQuadColors(std::vector<GLubyte>& rColors, Color nColor, GLfloat fTransparency);
+
+template<>
+inline void addQuadColors<GL_TRIANGLES>(std::vector<GLubyte>& rColors, Color nColor, GLfloat fTransparency)
+{
+    GLubyte nR, nG, nB, nA;
+    createColor(nColor, fTransparency, nR, nG, nB, nA);
+
+    rColors.insert(rColors.end(), {
+        nR, nG, nB, nA,
+        nR, nG, nB, nA,
+        nR, nG, nB, nA,
+        nR, nG, nB, nA,
+        nR, nG, nB, nA,
+        nR, nG, nB, nA,
+    });
+}
+
+inline void addLineSegmentVertices(std::vector<GLfloat>& rVertices, std::vector<GLfloat>& rExtrusionVectors,
+                                   glm::vec2 prevPoint, glm::vec2 prevExtrusionVector, GLfloat prevLength,
+                                   glm::vec2 currPoint, glm::vec2 currExtrusionVector, GLfloat currLength)
+{
+    rVertices.insert(rVertices.end(), {
+        prevPoint.x, prevPoint.y,
+        prevPoint.x, prevPoint.y,
+        currPoint.x, currPoint.y,
+        currPoint.x, currPoint.y,
+        prevPoint.x, prevPoint.y,
+        currPoint.x, currPoint.y,
+    });
+
+    rExtrusionVectors.insert(rExtrusionVectors.end(), {
+        -prevExtrusionVector.x, -prevExtrusionVector.y, -prevLength,
+         prevExtrusionVector.x,  prevExtrusionVector.y,  prevLength,
+        -currExtrusionVector.x, -currExtrusionVector.y, -currLength,
+        -currExtrusionVector.x, -currExtrusionVector.y, -currLength,
+         prevExtrusionVector.x,  prevExtrusionVector.y,  prevLength,
+         currExtrusionVector.x,  currExtrusionVector.y,  currLength,
+    });
+}
+
+inline glm::vec2 normalize(const glm::vec2& vector)
+{
+    if (glm::length(vector) > 0.0)
+        return glm::normalize(vector);
+    return vector;
+}
+
+inline glm::vec2 perpendicular(const glm::vec2& vector)
+{
+    return glm::vec2(-vector.y, vector.x);
+}
+
+inline float lineVectorAngle(const glm::vec2& previous, const glm::vec2& next)
+{
+    float angle = std::atan2(previous.x * next.y - previous.y * next.x,
+                             previous.x * next.x + previous.y * next.y);
+
+    return F_PI - std::fabs(angle);
+}
+
+}} // end vcl::vertex
+
+#endif // INCLUDED_VCL_INC_OPENGL_VERTEXUTILS_H
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */