diff -r 121a40d5e34c -r 8e1c9f18ae15 src/gl/vertexprogram.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/gl/vertexprogram.cpp	Tue Jul 27 16:29:00 2021 +0300
@@ -0,0 +1,115 @@
+#include "vertexprogram.h"
+#include "document.h"
+
+static const char vertexShaderSource[] = R"(
+#version 330 core
+
+layout (location = 0) in vec3 in_position;
+layout (location = 1) in vec3 in_color;
+uniform mat4 view;
+uniform mat4 projection;
+uniform mat4 model;
+smooth out vec3 ex_color;
+
+void main()
+{
+	gl_Position = projection * view * model * vec4(in_position, 1.0);
+	ex_color = in_color;
+}
+)";
+
+static const char fragmentShaderSource[] = R"(
+#version 330 core
+
+out vec4 color;
+smooth in vec3 ex_color;
+
+void main(void)
+{
+	color = vec4(ex_color, 1);
+}
+)";
+
+static constexpr int VERTICES_PER_OBJECT = 16;
+
+
+VertexProgram::VertexProgram(QObject *parent) :
+	AbstractBasicShaderProgram{parent}
+{
+}
+
+const char *VertexProgram::vertexShaderSource() const
+{
+	return ::vertexShaderSource;
+}
+
+const char *VertexProgram::fragmentShaderSource() const
+{
+	return ::fragmentShaderSource;
+}
+
+const void *VertexProgram::vertexData() const
+{
+	return this->data.data();
+}
+
+int VertexProgram::vertexSize() const
+{
+	return sizeof(Vertex);
+}
+
+int VertexProgram::vertexCount() const
+{
+	return this->data.size();
+}
+
+void VertexProgram::setupVertexArrays()
+{
+	for (int i : {0, 1})
+	{
+		this->program->enableAttributeArray(i);
+	}
+	const int stride = this->vertexSize();
+	this->program->setAttributeBuffer(0, GL_FLOAT, offsetof(Vertex, position), 3, stride);
+	this->program->setAttributeBuffer(1, GL_FLOAT, offsetof(Vertex, color), 3, stride);
+}
+
+GLenum VertexProgram::drawMode() const
+{
+	return GL_LINES;
+}
+
+QOpenGLBuffer::UsagePattern VertexProgram::usagePattern() const
+{
+	return QOpenGLBuffer::DynamicDraw;
+}
+
+void VertexProgram::build(const Document *document)
+{
+	constexpr float size = 1;
+	constexpr glm::vec3 color = {0.0, 1.0, 1.0};
+	this->data.clear();
+	document->applyToVertices([&](const glm::vec3& vertex, const std::set<ldraw::id_t>&)
+	{
+		reserveMore(this->data, VERTICES_PER_OBJECT);
+		this->data.push_back({vertex, color});
+		this->data.push_back({vertex + glm::vec3{size, -size, size}, color});
+		this->data.push_back({vertex, color});
+		this->data.push_back({vertex + glm::vec3{size, -size, -size}, color});
+		this->data.push_back({vertex, color});
+		this->data.push_back({vertex + glm::vec3{-size, -size, -size}, color});
+		this->data.push_back({vertex, color});
+		this->data.push_back({vertex + glm::vec3{-size, -size, size}, color});
+		this->data.push_back({vertex + glm::vec3{size, -size, size}, color});
+		this->data.push_back({vertex + glm::vec3{size, -size, -size}, color});
+		this->data.push_back({vertex + glm::vec3{size, -size, -size}, color});
+		this->data.push_back({vertex + glm::vec3{-size, -size, -size}, color});
+		this->data.push_back({vertex + glm::vec3{-size, -size, -size}, color});
+		this->data.push_back({vertex + glm::vec3{-size, -size, size}, color});
+		this->data.push_back({vertex + glm::vec3{-size, -size, size}, color});
+		this->data.push_back({vertex + glm::vec3{size, -size, size}, color});
+	});
+	this->buffer.bind();
+	this->buffer.allocate(this->vertexData(), this->vertexCount() * this->vertexSize());
+	this->buffer.release();
+}