_initMatrices() {
        // create our matrices, they will be set after
        const matrix = new Mat4();
        this._matrices = {
            world: {
                // world matrix (global transformation)
                matrix: matrix,
            },
            modelView: {
                // model view matrix (world matrix multiplied by camera view matrix)
                name: "uMVMatrix",
                matrix: matrix,
                location: this.gl.getUniformLocation(this._program.program, "uMVMatrix"),
            },
            projection: {
                // camera projection matrix
                name: "uPMatrix",
                matrix: matrix,
                location: this.gl.getUniformLocation(this._program.program, "uPMatrix"),
            },
            modelViewProjection: {
                // model view projection matrix (model view matrix multiplied by projection)
                matrix: matrix,
            }
        };
    }
Init our plane model view and projection matrices and set their uniform locations
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