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      "source": [
        "%gui qt"
      ]
    },
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      "metadata": {},
      "source": [
        "\n# Draw a Quad\n\nSimple example demonstrating showing a quad using a gloo Program.\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
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      },
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      "source": [
        "from vispy import gloo\nfrom vispy import app\nimport numpy as np\n\n# Create vertices\nvPosition = np.array([[-0.8, -0.8, 0.0], [+0.7, -0.7, 0.0],\n                      [-0.7, +0.7, 0.0], [+0.8, +0.8, 0.0, ]], np.float32)\n\n\nVERT_SHADER = \"\"\" // simple vertex shader\nattribute vec3 a_position;\nvoid main (void) {\n    gl_Position = vec4(a_position, 1.0);\n}\n\"\"\"\n\nFRAG_SHADER = \"\"\" // simple fragment shader\nuniform vec4 u_color;\nvoid main()\n{\n    gl_FragColor = u_color;\n}\n\"\"\"\n\n\nclass Canvas(app.Canvas):\n\n    def __init__(self):\n        super().__init__(keys='interactive')\n\n        # Create program\n        self._program = gloo.Program(VERT_SHADER, FRAG_SHADER)\n\n        # Set uniform and attribute\n        self._program['u_color'] = 0.2, 1.0, 0.4, 1\n        self._program['a_position'] = gloo.VertexBuffer(vPosition)\n\n        gloo.set_clear_color('white')\n\n        self.show()\n\n    def on_resize(self, event):\n        width, height = event.physical_size\n        gloo.set_viewport(0, 0, width, height)\n\n    def on_draw(self, event):\n        gloo.clear()\n        self._program.draw('triangle_strip')\n\n\nif __name__ == '__main__':\n    canvas = Canvas()\n    app.run()"
      ]
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